Merge pull request #23 from vuntz/release/stoney/master

Removed the single assignment block from constraints
Merge pull request #25 from vuntz/trivial

Fix use of non-existing variable
Merge pull request #12 from vuntz/haproxy

HA with HAProxy
Merge branch 'release/roxy/master' into sync-roxy

Conflicts:
	crowbar_framework/app/helpers/pacemaker_barclamp_helper.rb
	crowbar_framework/app/views/barclamp/pacemaker/_edit_attributes.html.haml
Fix duplicated code appearing after merge