Added AIX providers for logical_volume and filesystem types
Added attributes to filesystem type
Use the builtin which instead of the generic exec.
Merge pull request #44 from smithj4/lvm_support

Suppress facter warnings on systems that don't support LVM.
Merge pull request #43 from crayfishx/aix_support

Add AIX support for LVs and Filesystems
Use fully qualified volume paths
Implement 'instances' method for all LVM resources

This method makes it possible to use constructs like:
  resources { 'physical_volume': purge => true, noop => true, }
  resources { 'logical_volume':  purge => true, noop => true, }
  resources { 'volume_group':    purge => true, noop => true, }
Implement empty 'extents' method

It is required by 'instances' method.
There is no simple way to get LV size in extents,
so leave it empty for now.
Set default LV unit size to MB