Updated Lever for spring loaded Replicator Drive Block

This is an enhancement to the Spring-Loaded Replicator Drive Block (http://www.thingiverse.com/thing:53125) lever. This part eliminates the need for the top plate that holds the 6mm/0.25" filament guide tubing. Also, it has a window so you can access the drive pulley for inspection and cleaning. It uses the same hardware and other printed pieces as the original drive block.