Indexedredis

- Add copyToExternal which allows copying a model to a redis instance
other than the one specified for that model
- Add copyAllToExternal which allows copying the results of a filterset to
a redis instance other than that specified for the given model
- Fix inconsistant returns, pk should always be a string
- Rewrote internal save function to make more sense and allow forcing
multiple IDs
- Add reindex method which will rerun the indexes on a list of models. Use
this as MyModel.objects.reindex() if you add a field to INDEXED_FIELDS
array which is already existing field to add it to indexes.

- Add "exists" method for testing the existance of a primary key
- Add MANIFEST.in file (missed in 2.5.0 -- this is only difference)
- regen docs
- Replace example.py with a copy of test.py... not sure why there were two

- Add method, isIndexedRedisModel to see if a model extends
IndexedRedisModel
- Add method, hasUnsavedChanges which returns bool of if there are
unsaved changes. Remember, you can see all (local) changes with
getUpdatedFields
- Implement __str__ and __repr__
Examples of __str__:
(Pdb) str(z)
'<Song obj _id=24 at 0x7f3c6a3a4490>'
(Pdb) z.artist = 'New Artist'
(Pdb) str(z)
'<Song obj _id=24 (Unsaved Changes) at 0x7f3c6a3a4490>'
- Examples of __repr__ - This will build a constructor.
eval(repr(obj)) should build the same object.
(Pdb) print repr(song)
Song(_id="6", album='Super Tracks', description='Super
Nintendo', copyright='Copyright 2014 (c) Cheese Industries',
title='Nintendo 2', artist='Mega Men', track_number='2',
duration='1:55')
- Implement a .copy function for copying models. Takes a single
argument, copyPrimaryKey. If True, any saves on the copy will change
the original model. Keep in mind this may cause sync issues. If False
(default) only the data is copied.
- Implement __setstate__ and __getstate__ to make objects support
being pickled and loaded from pickle strings efficiently.
- Implement "reload" function on a model. This fetches any updates
from Redis, if available, and returns a list of field names that were
updated.

- Add some more docstring
- make getNextID and peekNextID private methods. They should only be
used internal.
- Regenerate docs
- Remove argument on getEncoding -- didn't do anything

- Change Model.objects.filter(...).delete to fetch minimal data (only
indexed fields) instead of entire objects, so deleting is more
efficent.
- Add getOnlyFields, allOnlyFields, allOnlyIndexedFields, etc for
getting partial objects
- Increase efficency of getMultiple function
- Add more docstrings
- Distribute pydoc as /IndexedHtml.html
- Allow deleter to delete by primary key only on (Model.deleter)

- Fix invalid variable