Parameterize home permissions

Allow home permissions to be overridden in Hiera data.
Respect default OS umask value for home directory permissions

RHEL has a default umask of 077 for new home directories. Debian seems to use 022. Default value set to err on the safe side.
Provide osfamily fact for rspec tests
Allow Hiera merge lookup types

I believe [HI-118](https://tickets.puppetlabs.com/browse/HI-118) prevents merge lookup types from operating as expected when hiera_hash or hiera_array is called within the class parameters section.

This prevents the $users variable from being passed in as a parameter, but shouldn't we be modeling this data in Hiera anyway?
version bump
Merge branch 'release/v1.0.0'