Fix Popcorn demo RangeControler bug

Added a swap method in the RangeController (very similar to its splice
method). This fixes an issue where the Popcorn demo was not selecting
the first movie on load.
Removed console logs and fixed tabs
Fixed tabs again
Rewrote RangeController.splice in terms of swap and renamed one of swap's arguments

RangeController.splice might not be necessary
Removed RangeController.splice (unused)
Merge pull request #1486 from cdebost/master

Fix RangeController bug showing in Popcorn demo