Implemented __deepcopy__ to avoid infinite recursion in __getattr__ while deepcopying a Choices instance
Added deepcopy test
Refactor to make sure get_subclass() is on QuerySet

There's an edge case where you might want to call get_subclass() on a
QuerySet the same way you can call get() after you have already called
various filter/exclude methods.
Add test to verify get_subclass() on QuerySet
Merge pull request #82 from tswicegood/fix-get_subclass

Refactor to make sure get_subclass() is on QuerySet
Update AUTHORS and changelog.
adding 'when' parameter to MonitorField
only accepting iterables to the when field
Merge pull request #85 from filipeximenes/master

Adding 'when' parameter to MonitorField
Merge branch 'master' into fix-choices-deepcopy

* master: (23 commits)
  only accepting iterables to the when field
  adding 'when' parameter to MonitorField
  Update AUTHORS and changelog.
  Add test to verify get_subclass() on QuerySet
  Refactor to make sure get_subclass() is on QuerySet
  Fixed indexing into Choices so its useful.
  Fix bug with child/grandchild select_subclasses in Django 1.6+; thanks Keryn Knight.
  fixed code block
  Bump version for dev.
  Bump version for 1.5.0 release.
  Add option-groups capability to Choices.
  Add Changelog note about Choices equality/addition.
  Added tests to improve coverage
  Alphabetised authors
  Removed redundant inequality method on Choices
  Moved documentation for Choices field to the right place
  Corrected typo
  Added self to Authors file
  Added equality methods to Choices objects, and overrode + for Choices for easy concatenation with other Choices and choice-like iterables. Also wrote tests for them, and extended the readme to reflect this
  Fix typo noted by @silonov
  ...

Conflicts:
	model_utils/choices.py
Merge branch 'fix-choices-deepcopy'

* fix-choices-deepcopy:
  Added deepcopy test
  Implemented __deepcopy__ to avoid infinite recursion in __getattr__ while deepcopying a Choices instance
Update AUTHORS and changelog.
Use full name in AUTHORS.
Flesh out the backwards-incompatibility note about indexing Choices.
Implemented #44 - passing Model classes to InheritanceManager's select_subclasses