Notify SockJS client when connecting to a STOMP URL using HTTPS

[dougreese]

The sockjs_client package was modified to work better over HTTPS. See issue: nelsonsilva/sockjs-dart-client#10

This package must notify the sockjs_client when it should use a secure connection in its internal protocol detection routines. Ideally sockjs_client would do this automatically, but some non-trivial refactoring would likely be involved.

There is no change to the behavior of code using this package.

Note: The sockjs_client dependency is temporary until the updated sockjs_client package is updated on pub. If/when that happens, change the sockjs_client dependency from

  sockjs_client:
    git:
      url: git@github.com:dougreese/sockjs-dart-client.git
      ref: 0.3.0

to

  sockjs_client: '>= 0.3.0'

[tomikiss]

Thanks for this.