Typo Fix In decoderawtransaction Help: s/txid/hex/

Help text appears to have been copy/pasted from getrawtransaction,
so it erroneously asked for a txid where rawtransaction hex should appear.

Remove lines which were copy/pasted from getrawtransaction but which
aren't displayed by decoderawtransaction.

Rebased-By: Wladimir J. van der Laan <laanwj@gmail.com>
Rebased-From: 5cc0133 80c521e
Github-Pull: #4106

src/rpcrawtransaction.cpp

@@ -400,12 +400,11 @@ Value decoderawtransaction(const Array& params, bool fHelp)
             "\nReturn a JSON object representing the serialized, hex-encoded transaction.\n"
 
             "\nArguments:\n"
-            "1. \"txid\"      (string, required) The transaction hex string\n"
+            "1. \"hex\"      (string, required) The transaction hex string\n"
 
             "\nResult:\n"
             "{\n"
-            "  \"hex\" : \"data\",       (string) The serialized, hex-encoded data for 'txid'\n"
+            "  \"txid\" : \"id\",        (string) The transaction id\n"
-            "  \"txid\" : \"id\",        (string) The transaction id (same as provided)\n"
             "  \"version\" : n,          (numeric) The version\n"
             "  \"locktime\" : ttt,       (numeric) The lock time\n"
             "  \"vin\" : [               (array of json objects)\n"
@@ -437,10 +436,6 @@ Value decoderawtransaction(const Array& params, bool fHelp)
             "     }\n"
             "     ,...\n"
             "  ],\n"
-            "  \"blockhash\" : \"hash\",   (string) the block hash\n"
-            "  \"confirmations\" : n,      (numeric) The confirmations\n"
-            "  \"time\" : ttt,             (numeric) The transaction time in seconds since epoch (Jan 1 1970 GMT)\n"
-            "  \"blocktime\" : ttt         (numeric) The block time in seconds since epoch (Jan 1 1970 GMT)\n"
             "}\n"
 
             "\nExamples:\n"