767 bindings docs minor

fixes #767 

This is the merge request for adding docco for can/view/bindings.  There are a few changes/things to discuss.

1. The docco itself
1. All API docs and examples were moved to the docs folder
1. I changed bindings.js so it returns the `special` object, so that it can be extended, similar to $.event.special.  I added a test showing that and docs on the can-EVENT page for special events.
1. can-true-value and can-false-value don't have a test or any docs explaining how to use them.  I tried to think of a usage example from the code, but couldn't figure out what it would be used for.  Should we get rid of this?  Is it useful for something?