First set of fixes for Dart 1.0 compatibility
Finish to fix last warnings and errors, now I need to test this with a Node or Spring 4 backend ...
Updated pubspec.yml + remove unused import
Fix after basic testing (Websocket only with echo service) against SockJS node server 0.3.8
Take in account @nelsonsilva feedbacks
Merge pull request #1 from sdeleuze/master

Dart 1.0 fixes