add watching var to prevent resize after kill has been made

This is probably due to a timing issue of matchmedia and $(window).resize events.   Occasionally the last resize.ehc event will get triggered one last time after the instance has bee .kill()ed via matchMedia (Harvey/Enquire).   To solve this, I have added a 'watching' var which indicates if we have the resize event bound or if it has been killed.   This way we can quickly escape the resize event handler if we aren't actually supposed to be watching for resize events.

Oh, and I also removed a trailing console.log ;)