Merge pull request #6 from nimnull/master

Added support for GAE python env without future_builtins
Missing comma
Add "Key" to __all__
Merge pull request #7 from tailhook/patch-1

Missing comma and "Key" in __all__
Fix doctests for python3.3 (or PYTHONHASHSEED=random)
Merge pull request #9 from tailhook/python3.3_tests

Fix doctests for python3.3 (or PYTHONHASHSEED=random)
Version
Added extra dependencies. Updated str_types for 2.x versions
Fixed str types definition. Added entry points for RFC3339 DateTeime and bson.ObjectId