[conformal/btcd] 3266bf: Convert to use gorilla websockets package.

[Dave Collins]

  Branch: refs/heads/master
  Home:   https://github.com/conformal/btcd
  Commit: 3266bf6a8d8c061aeab9900cec66a52803373bb8
      
https://github.com/conformal/btcd/commit/3266bf6a8d8c061aeab9900cec66a52803373bb8
  Author: Dave Collins <da...@conformal.com>
  Date:   2014-06-07 (Sat, 07 Jun 2014)

  Changed paths:
    M rpcserver.go
    M rpcwebsocket.go

  Log Message:
  -----------
  Convert to use gorilla websockets package.

Also, since the new websoscket package allows the message type to be set
independently from the type of the variable, remove the casts between
strings and []byte in the websocket read/write paths.  This avoids extra
copies thereby reducing the garbage generated.

Closes #134.