HAProxy support for heat-api*

adapt helper and model to prepare cluster info

db password must not be created in the cookbook, but in crowbar
(so that it is common for the cluster nodes)

increased schema-revision

use the library functions for shared code
Remove unused openssl bits
Depend on crowbar-pacemaker cookbook
Use CrowbarPacemakerHelper.haproxy_servers_for_service
Include the HA recipe after having created the service

This is the current model we're following (it will allow stopping the
service before restarting them with pacemaker, when required).
Merge pull request #1 from vuntz/haproxy

Cleanups required before merging
Update constraints so that heat-server role can be assigned to cluster
Merge pull request #2 from vuntz/haproxy

Update constraints so that heat-server role can be assigned to cluster
Merge pull request #40 from jsuchome/haproxy

Work with keystone behind haproxy + haproxy for heat-api*