More fixes for apache 2.4

modified:   manifests/init.pp
	load mpm
modified:   manifests/mod/cgi.pp
	load cgid if not a prefork mpm
modified:   manifests/mod/default.pp
	move mpm loading into it's own class so default setups still work
	add more required modules so balancer works
new file:   manifests/mod/mpm.pp
	put mpm loading here
modified:   manifests/params.pp
	add class var for setting mpm
	load thread safe version of php if using a non prefork mpm
modified:   templates/httpd.conf.erb
modified:   templates/test.vhost.erb
modified:   templates/vhost-default.conf.erb
modified:   templates/vhost-proxy.conf.erb
	use 2.4 specific access settings