Add MiqWidget importing/exporting

Related to Bugzilla 1115106
https://bugzilla.redhat.com/show_bug.cgi?id=1115106

@gmcculloug @dclarizio @h-kataria Please Review.

Also note that the styling for the slick grid stuff is off, but I figured that could be fixed after this is in.
I can't foresee any but alas, I really haven't been in rails validations in a long time.  I guess the intention is allow the same name schedule for different "towhat" values.  So, I don't think we'd have existing rows with the same name for the same "towhat" values... Unless I'm not understanding.