Created decorators for memcache

So I did some poking around in the ndb model.  Turns out we can't use it the way we intended.
http://stackoverflow.com/questions/14401682/ndb-caching-not-working-on-google-app-engine

However I wrote some wrappers that make it easy to add memcaching to any model. :smile: 

I guess I'm looking for input from you.  If you don't like it we can throw it out, because I don't think it looks pretty.  However, this should make reading from the datastore faster!