Add init class
Merge pull request #52 from mcanevet/feature/init

Add init class
Prepare a 0.3.0 release.
Merge pull request #53 from apenney/021-release

Prepare a 0.3.0 release.
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, }
Set default LV unit size to MB