Merge pull request #1 from benjreinhart/master

Filter our null and undefined query params
Merge pull request #2 from benjreinhart/master

Added VERSION constant and bumped version
Exposing addRoute helper.
Forgot to version bump the comment.
Guard against Backbone.history being undefined.
Only try to prepend root on named routes that are auto-generated via the router.
Removing unused variable.
Version bump.
Guarding against empty root.