add support for scientific linux
Merge pull request #12 from jhoblitt/scientificlinux

add support for scientific linux
fixing variables in templates
fixing variables in apache2.conf.erb template
missed @ in variable puppet_site
missed @ in variable certname
fixing missing characters
Merge remote-tracking branch 'ppouliot/master' into hsmaster_new_apache

Conflicts:
	templates/apache2.conf.erb
	templates/puppet.conf-common.erb
	templates/puppet.conf-master.erb
load mod_proxy{,_http} the new pl-apache way.
migrate to pl-apache way for SSL setup.
Remove servername, listen, documentroot directives and virtual host
declerations.
fix CA file paths
define ssl_certs_dir for clarity
Add missing module.
fix CA path which was accodentally removed in 6671dce7
Set servername for vhost.  I decided not to rename the resource in order
to make updating easier.
Use native apache::vhost means of setting RequestHeaders
Merge pull request #2 from hubspotdevops/hsmaster_new_apache

Hsmaster for pl-apache v0.9.0