Add httpproxy role

This code adds a new layout capable of installing haproxy.

- adds httpproxy node in site.pp
- adds rjil::http_proxy profile
- adds it as a consul bootstrap node (required
  for deploying a 1 node cluster)
- adds dependencies

Also, this will probably not work with gate test
b/c env_http(s)_proxy needs to be set from
jenkins
Merge pull request #239 from bodepd/test_proxy

Add httpproxy role