Start refactoring of the trigger system:

- Move each trigger handler into its own file
- Add dictionary helper classes for easier reading and writing of dict-based data
- Extract the web hook payload -> internal representation building for each trigger system
- Add tests for this transformation
- Remove support for Github archived-based building

endpoints/bitbuckettrigger.py

@@ -3,7 +3,8 @@ import logging
 from flask import request, redirect, url_for, Blueprint
 from flask.ext.login import current_user
 
-from endpoints.trigger import BitbucketBuildTrigger, BuildTriggerHandler
+from buildtrigger.basehandler import BuildTriggerHandler
+from buildtrigger.bitbuckethandler import BitbucketBuildTrigger
 from endpoints.common import route_show_if
 from app import app
 from data import model