added groups + member invites
removing members + add group_id to bills
Merge remote-tracking branch 'origin/add_groups' into alain_integration
check current_user with tag owner
tags cant be blank + description uniquess for each user
added groups validation
javascript added containers
added username to user, used to login and invite to groups
Added select box for users to bills/new
Merge branch 'alain_integration' into tom_integration

Conflicts:
	app/assets/javascripts/custom.js
	app/controllers/bills_controller.rb
	app/views/bills/new.html.erb