removed commotion-splash functionality.

All commotion splash control has been moved to the commotion-splash repo. The basic menu page will remain in this repository until after the R1.1 release when there will be time to ensure that moving that to splash, and having an install without splash, will not break EVERYTHING

See: https://github.com/opentechinstitute/luci-commotion-splash/pull/26 for instructions