Move appropriate methods to their respective objects to be more object oriented

[paltman]

It will get unweildy to have all the methods on the Connection object, not to mention it makes more a more clunky api.

>>> from pybrightcove.connection import Connection
>>> video = Connection().create_video()
>>> video.name = "....."   ## Set properties
>>> video.save()  ## Call the create_video API here to upload/create the video

>>> playlist = Connection().find_playlist_by_id(1342)
>>> playlist.some_properties   ## modify the playlist
>>> playlist.save()  ## call the update api method

[paltman]

first, let's get the api at near 100% coverage and then we can invert the methods to be better suited for more natural python API consumption.

[paltman]

this is in progress already