Update manifests/passenger/gem.pp

provide a way for puppet to ensure that the version of ruby required for passenger is a pre-requisite
Add compatability with puppet-stdlib

  - ensure_packages function
Add Amazon to centos group

so it works with AWS instances
Remove sendmail/mailx, not required
Removed uncompatible gem install flag

The latest version of gem removed the flag "includes-dependencies".
It's now the default behavior in gem 2.0.0
Merge pull request #67 from EmpireOne/master

Remove uncompatible flag in gem 2.0.0
Merge pull request #66 from domcleal/no-mta

Remove sendmail/mailx, not required
Merge pull request #65 from sinajahan/master

Added Amazon to centos group dependencies
Merge pull request #60 from angusscown/master

passenger ruby version requirement
Merge pull request #64 from paulche/master

Conflicts:
	manifests/dependencies/centos.pp
	manifests/dependencies/oraclelinux.pp