cleanup and version bump

Signed-off-by: Peter T. Brown <[email protected]>

Regenerate gemspec for version 0.7.0

Regenerate gemspec for version 0.6.3

Regenerate gemspec for version 0.6.2

Regenerate gemspec for version 0.6.1

Regenerate gemspec for version 0.6.0

Adding caching of labels before save, dynamic setters and getters to …

…support label_sets defined at runtime, and moving label sets to labels from labelings.

Signed-off-by: Peter T. Brown <[email protected]>