There is lack of CORS (XHR proxy) support for certain HTTP verbs.

This (presumably) adds support for the rest of the verbs, which were
left out when the proxy was re-written :-( (there definitely could have
been more testing in place for this, alas, resources..).

This fixes GitHub issue:

https://github.com/blackberry/Ripple-UI/issues/693
The OPTIONS verb was left out in the previous (XHR proxy fix) commit.

It is also an HTTP verb that should be supported by CORS (in the xhr
proxy).

I hastily pushed commit 8462f02fe161f8bf75379a933f62ccefd26903b9
and missed this.
In order to deploy to Heroku, Jasmine (submodule) needs to be removed.
There should be a Procfile to deploy to Heroku with.