* server: fixes#691, add event for exposing browser launch args
- enable special handling of ‘—load-extension’
- add e2e / integration / unit tests
- handle both chrome + electron cases
* server: iterate on failing tests, don't strip electron options else we lose valuable properties
- add better debugging
* server: fix failing tests, browsers needed
* server: send in a complete browser object for 'before:browser:launch'
- useful for doing conditional things with version and/or path
Brian Mann