Anet A8 Frame Back Brace w/Y-Axis Belt Tension Rods - 25mm added

This is a remix of the Back Frame brace from https://www.thingiverse.com/thing:2118713 - where 25mm has been added in length in order to accommodate the modification for a larger heated bed as listed in https://www.thingiverse.com/thing:2251940

This is still work in progress, and other parts for attaching the side of the original frame to the original back panel is probably needed. The bracket has not been test-printed yet - it will happen once I get the larger heated bed.