New Collection class

It will replace Feed and will be able to handle most collections
WIP collections everywhere
remove special collections and just use Collection
WIP Feed (was Collection)

Rename Collection class to Feed again, Collection class name is better
used for objects with objectType 'collection', which confusingly
are the object items of api/user/<username>/lists/person

Removed PyPump.{Followers,Following,List}, can now be found as
Person.{followers, following, lists}
TODO: pypump/models/list.py needs to be rewritten to Collection class
Person: change set_cc
Collection class, will replace List
Lists and Collections

Collection.{add,remove,delete}()
Lists.create()
deleted pypump/models/list.py
Fix comments/likes/shares

Forgot to change from Collection to Feed in models/__init__.py when
renaming Collection to Feed
model._post_activity have a unserialize=bool which defaults to True, we
dont want to unserialize when response doesnt have same objecttype as self
Prevent exception in inbox on deleted collections
Merge pull request #63 from kabniel/collection

Feeds and Collections
Reuse PyPump.me to speed up local note creation
Reuse PyPump.me in local comment creation too
Clean up Person
Person.update(display_name=None, summary=None)

method for updating a Person's details, only name and bio for now
remove self.VERB from Note,Comment
Person.lists['listname'] returns collection

Person.lists will now try to return a collection when called with
Person.lists['listname']

Also change Collection.__str__ to return Collection.display_name if set
update docs
fix grammar in docs