backport from epics: break down menu generating code

Conflicts:

	app/controllers/rb_master_backlogs_controller.rb
correct "new story" menu for shared releases
Merge branch 'releases3' into epic/master

Conflicts:
	app/controllers/rb_master_backlogs_controller.rb
WIP start rearranging epicboard
render releases into epicboard
render epicboard using master backlogs page data
epicboard shows only epics like product backlog would - project.self and descendants
Merge branch 'epic/epicboard' into epic/master