CTC Heated Build Platform Thermistor Fix

Many, many owners find that the Heated Build Platform on their CTC Dual Printer (which is a clone of the Flashforge Creator, which is in itself a clone of the Makerbot Replicator Dual), is woefully badly calibrated.

The HBP is based on the original Replicator HBP ( http://www.thingiverse.com/thing:16061 ), but the PCB layout is tweaked to make space for a largish (~7mm) thermistor, or a 1206 SMD part (only 1 should be fitted though).

In many ways, it doesn't really matter if the displayed