Extend images actions functionality

- add get_info_images action
- add ability to specify image_id, image_name or images_list to action
- change checking of existing images on destination cloud in the deploy
  method of glance_image resource from name to checksum
- move image actions from base to os
- move __patch_image staticmethod to glance_image resource
- fix some pep8 issues
Merge pull request #14 from miarmak/images_actions

Extend images actions functionality