Make GQ server side not depends on gwt-servlet not gwt-dev

Adding org.json dependency since we depend on it, and 2.7
uses a rebased version of android.json. We will have this
dependency in snapshot until we replace json usage in server
side, but we have to remove before releasing gquery.
Merge pull request #299 from manolo/master

Make GQ server side not depends on gwt-servlet not gwt-dev
Events listener using Predicate selectors instead of cssSelectors

This is a work around of the performance problem caused by closest->is(cssSelector) so you can implement your own Predicate filter and skip the closest call. This problem get worst when the target event is a child of a element with lot of children, because the current implementation uses $(e.getParentNode(),cssSelector).first()==e to check if e satisfies cssSelector.