Add basic mention functionality

Conflicts:
	lineman/app/js/services/restful_service.coffee
	lineman/app/templates/add_comment.haml
Add basic mention functionality
Merge pull request #1744 from loomio/angular-mentions

Add basic mention functionality
Fix comment form for mentions
Merge branch 'angular' into angular-groups

Conflicts:
	config/routes.rb
	lineman/app/js/models/group_model.coffee
Add members to group page