Mark Task #1 as complete (apache#133)

Author: cbb330

task_list.json

@@ -12,7 +12,7 @@
       "cmake --build cpp/build --target arrow-orc-adapter-test -j8 succeeds",
       "cd cpp/build && ctest --output-on-failure -R arrow-orc-adapter-test passes"
     ],
-    "status": "pending",
+    "status": "complete",
     "depends_on": [],
     "notes": "Look at adapter.cc Impl class for the reader_ member. The orc::Reader::getStatistics() returns unique_ptr<Statistics>, and getStripeStatistics(i) returns unique_ptr<StripeStatistics>. Call ->getColumnStatistics(colId) on the result to get const ColumnStatistics*. Use dynamic_cast to detect the typed subclass."
   },