diff --git a/package-lock.json b/package-lock.json
index 2da3ba1..b5d0555 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -526,7 +526,8 @@
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/assert-plus/-/assert-plus-1.0.0.tgz",
       "integrity": "sha1-8S4PPF13sLHN2RRpQuTpbB5N1SU=",
-      "dev": true
+      "dev": true,
+      "optional": true
     },
     "assign-symbols": {
       "version": "1.0.0",
@@ -1561,6 +1562,7 @@
       "resolved": "https://registry.npmjs.org/combined-stream/-/combined-stream-1.0.8.tgz",
       "integrity": "sha512-FQN4MRfuJeHf7cBbBMJFXhKSDq+2kAArBlmRBvcvFE5BB1HZKXtSFASDhdlz9zOYwxh8lDdnvmMOe/+5cdoEdg==",
       "dev": true,
+      "optional": true,
       "requires": {
         "delayed-stream": "~1.0.0"
       }
@@ -2488,7 +2490,8 @@
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/delayed-stream/-/delayed-stream-1.0.0.tgz",
       "integrity": "sha1-3zrhmayt+31ECqrgsp4icrJOxhk=",
-      "dev": true
+      "dev": true,
+      "optional": true
     },
     "depd": {
       "version": "1.1.2",
@@ -2632,18 +2635,26 @@
       "dev": true
     },
     "elliptic": {
-      "version": "6.5.1",
-      "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.5.1.tgz",
-      "integrity": "sha512-xvJINNLbTeWQjrl6X+7eQCrIy/YPv5XCpKW6kB5mKvtnGILoLDcySuwomfdzt0BMdLNVnuRNTuzKNHj0bva1Cg==",
+      "version": "6.5.4",
+      "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.5.4.tgz",
+      "integrity": "sha512-iLhC6ULemrljPZb+QutR5TQGB+pdW6KGD5RSegS+8sorOZT+rdQFbsQFJgvN3eRqNALqJer4oQ16YvJHlU8hzQ==",
       "dev": true,
       "requires": {
-        "bn.js": "^4.4.0",
-        "brorand": "^1.0.1",
+        "bn.js": "^4.11.9",
+        "brorand": "^1.1.0",
         "hash.js": "^1.0.0",
-        "hmac-drbg": "^1.0.0",
-        "inherits": "^2.0.1",
-        "minimalistic-assert": "^1.0.0",
-        "minimalistic-crypto-utils": "^1.0.0"
+        "hmac-drbg": "^1.0.1",
+        "inherits": "^2.0.4",
+        "minimalistic-assert": "^1.0.1",
+        "minimalistic-crypto-utils": "^1.0.1"
+      },
+      "dependencies": {
+        "bn.js": {
+          "version": "4.12.0",
+          "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-4.12.0.tgz",
+          "integrity": "sha512-c98Bf3tPniI+scsdk237ku1Dc3ujXQTSgyiPUDEOe7tRkhrqridvh8klBv0HCEso1OLOYcHuCv/cS6DNxKH+ZA==",
+          "dev": true
+        }
       }
     },
     "emoji-regex": {
@@ -3053,7 +3064,8 @@
       "version": "1.3.0",
       "resolved": "https://registry.npmjs.org/extsprintf/-/extsprintf-1.3.0.tgz",
       "integrity": "sha1-lpGEQOMEGnpBT4xS48V06zw+HgU=",
-      "dev": true
+      "dev": true,
+      "optional": true
     },
     "fast-deep-equal": {
       "version": "2.0.1",
@@ -4322,7 +4334,8 @@
       "version": "0.1.1",
       "resolved": "https://registry.npmjs.org/jsbn/-/jsbn-0.1.1.tgz",
       "integrity": "sha1-peZUwuWi3rXyAdls77yoDA7y9RM=",
-      "dev": true
+      "dev": true,
+      "optional": true
     },
     "jsesc": {
       "version": "0.5.0",
@@ -8074,7 +8087,8 @@
       "version": "0.14.5",
       "resolved": "https://registry.npmjs.org/tweetnacl/-/tweetnacl-0.14.5.tgz",
       "integrity": "sha1-WuaBd/GS1EViadEIr6k/+HQ/T2Q=",
-      "dev": true
+      "dev": true,
+      "optional": true
     },
     "type-is": {
       "version": "1.6.18",
@@ -8536,7 +8550,8 @@
             "ansi-regex": {
               "version": "2.1.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "aproba": {
               "version": "1.2.0",
@@ -8557,12 +8572,14 @@
             "balanced-match": {
               "version": "1.0.0",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "brace-expansion": {
               "version": "1.1.11",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "balanced-match": "^1.0.0",
                 "concat-map": "0.0.1"
@@ -8577,17 +8594,20 @@
             "code-point-at": {
               "version": "1.1.0",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "concat-map": {
               "version": "0.0.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "console-control-strings": {
               "version": "1.1.0",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "core-util-is": {
               "version": "1.0.2",
@@ -8704,7 +8724,8 @@
             "inherits": {
               "version": "2.0.3",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "ini": {
               "version": "1.3.5",
@@ -8716,6 +8737,7 @@
               "version": "1.0.0",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "number-is-nan": "^1.0.0"
               }
@@ -8730,6 +8752,7 @@
               "version": "3.0.4",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "brace-expansion": "^1.1.7"
               }
@@ -8737,12 +8760,14 @@
             "minimist": {
               "version": "0.0.8",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "minipass": {
               "version": "2.3.5",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "safe-buffer": "^5.1.2",
                 "yallist": "^3.0.0"
@@ -8761,6 +8786,7 @@
               "version": "0.5.1",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "minimist": "0.0.8"
               }
@@ -8841,7 +8867,8 @@
             "number-is-nan": {
               "version": "1.0.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "object-assign": {
               "version": "4.1.1",
@@ -8853,6 +8880,7 @@
               "version": "1.4.0",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "wrappy": "1"
               }
@@ -8938,7 +8966,8 @@
             "safe-buffer": {
               "version": "5.1.2",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "safer-buffer": {
               "version": "2.1.2",
@@ -8974,6 +9003,7 @@
               "version": "1.0.2",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "code-point-at": "^1.0.0",
                 "is-fullwidth-code-point": "^1.0.0",
@@ -8993,6 +9023,7 @@
               "version": "3.0.1",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "ansi-regex": "^2.0.0"
               }
@@ -9036,12 +9067,14 @@
             "wrappy": {
               "version": "1.0.2",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "yallist": {
               "version": "3.0.3",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             }
           }
         },