Add verify_ssl and proxy_address bundle options.

This will allow setting these options on the HipChat service.
The HipChat package requirement in Composer is updated to dev.
This is needed because the verify_ssl en proxy options are not present
in the latest stable tag.
Yeah, something like that. I guess it would make more sense for the ``proxy_address`` than the ``verify_ssl`` (which is true by default).

But I think we'll leave it (keep the calls in the service XML) for now :-)