Do not use a default DHCP range

Providing a free lease by default is intrusive and not needed for
foreman to function.
Simplify proxydhcp inline templates
Add Modulefile and pre-reqs for Puppet Forge
Fix name of puppet confdir parameter
Use RC repo
Generate puppet_conf path from puppet confdir
Validate parameters
#2577 syslinux memdisk support
Use @var for puppet 3.2 compatibility
Release 1.2.0-rc2