Update http_parser.rb dep to 0.6.0.pre2

em-http-request needs to be updated to 1.1.1 for
dependency compatability

em-websocket-client added to spec suite since em-http-request
1.x does not support websockets
Merge pull request #106 from movitto/update-dependencies

Update http_parser.rb dep to 0.6.0.pre2