Add Consul support

Add the basic Consul framework and monitor etcd as an example.
Handle consul discovery token in Vagrantfile, too.
Add separate vagrant env for lxc due to network differences
Add a tags argument to be passed on to consul
Add checks for ssh, mysql, haproxy, keystone, etc.
Only trigger consul-reload on systems with Consul
Fix indentation style (tabs vs. spaces)
Give preference to listen_ports for monitoring
Choose better IPs for things
Merge pull request #70 from sorenh/consul

Add Consul support