Added Crash on Provider ID Conflict

Added a check so that Dimensional Doors crashes if another registers our
provider IDs. This will show people that something needs fixing instead
of us risking strange bugs.
Updated Rift Blade Code

Removed duplicate code from ItemRiftBlade. It was code that duplicated
the functionality of ItemSword since ItemRiftBlade didn't extend
ItemSword originally. Also updated the tooltip text to remove mentions
of the old door-rotating ability. That's not provided anymore since
doors are easily broken and replaced now. Extended teleport range
slightly.