Evas smart: Mark all smart clippers as no_render

Evas smart: Mark all smart clippers as no_render

This allows doing ugly things such as setting a clipper/mask
on any smart object, without having to worry about seeing a
white rectangle cover the whole screen.

While the above scenario is not a great idea (bypass elementary in
its handling of the clipper), having a big white rect covering the
entire UI seems even worse.

I wonder if elm objects shouldn't simply allow user clippers, and
somehow manage them along with the smart object internal clipper.