Deal with Passenger moving the Apache module

As best I can tell, for Passenger

    $version >= 4.0.0           ${gemdir}/buildout/apache2/mod_passenger.so
    3.9.0 <= $version < 4.0.0   ${gemdir}/libout/apache2/mod_passenger.so
    $version < 3.9.0            ${gemdir}/ext/apache2/mod_passenger.so

This commit also specifies $HOME in execs of rvm commands; not having it
set was breaking on EC2 instances.  Finally, I switch to the `osfamily`
fact instead of `operatingsystem` to add compatibility with additional
platforms.
Adding sigil to remove deprecation warning