Remove some TODO's

I've implemented some change in gwtquery needed for the tooltip plugin:
https://github.com/gwtquery/gwtquery/pull/4
https://github.com/gwtquery/gwtquery/pull/7
https://github.com/gwtquery/gwtquery/pull/8

They allow removing some TODO's in tooltip plugin code.

Please DO NOT MERGE this pull request before GwtQuery 1.2.1 is released !