rename namespaces and remove "ipfs" alias for "p2p" (#283)

Previously, we called these foo-ns. Now we just call them foo (the fact
that they're "namespaces" is implicit.

This way, the path component always matches the multicodec name (for
both multiaddr and other path types).

Author: Stebalien

table.csv

@@ -81,10 +81,10 @@ md4,                            multihash,      0xd4,           draft,
 md5,                            multihash,      0xd5,           draft,
 decred-block,                   ipld,           0xe0,           draft,     Decred Block
 decred-tx,                      ipld,           0xe1,           draft,     Decred Tx
-ipld-ns,                        namespace,      0xe2,           draft,     IPLD path
-ipfs-ns,                        namespace,      0xe3,           draft,     IPFS path
-swarm-ns,                       namespace,      0xe4,           draft,     Swarm path
-ipns-ns,                        namespace,      0xe5,           draft,     IPNS path
+ipld,                           namespace,      0xe2,           draft,     IPLD path
+ipfs,                           namespace,      0xe3,           draft,     IPFS path
+swarm,                          namespace,      0xe4,           draft,     Swarm path
+ipns,                           namespace,      0xe5,           draft,     IPNS path
 zeronet,                        namespace,      0xe6,           draft,     ZeroNet site address
 secp256k1-pub,                  key,            0xe7,           draft,     Secp256k1 public key (compressed)
 dnslink,                        namespace,      0xe8,           permanent, DNSLink path
@@ -109,7 +109,6 @@ utp,                            multiaddr,      0x012e,         draft,
 unix,                           multiaddr,      0x0190,         permanent,
 thread,                         multiaddr,      0x0196,         draft,     Textile Thread
 p2p,                            multiaddr,      0x01a5,         permanent, libp2p
-ipfs,                           multiaddr,      0x01a5,         draft,     libp2p (deprecated)
 https,                          multiaddr,      0x01bb,         draft,
 onion,                          multiaddr,      0x01bc,         draft,
 onion3,                         multiaddr,      0x01bd,         draft,

validate.py

@@ -4,20 +4,10 @@
 import sys
 import re
 
-# We have some duplicates
-ALIAS_TABLE = [
-    {"ipfs", "p2p"},
-]
-
 def check(fname='table.csv'):
     class CheckError(Exception):
         pass
 
-    aliases = {}
-    for nameset in ALIAS_TABLE:
-        for name in nameset:
-            aliases[name] = nameset
-
     success = True
     with open(fname) as table:
         tablereader = csv.reader(table, strict=True, skipinitialspace=False)
@@ -84,11 +74,6 @@ class CheckError(Exception):
                     names[name] = code
 
                 if code in codes:
-                    dup = codes[code]
-                    if name in aliases:
-                        if dup in aliases[name]:
-                            # Skip aliased names
-                            continue
                     raise CheckError(
                         f"found duplicate for code {hex(code)} "
                         f"for '{codes[code]}' and '{name}'"