I've just assembled an Adafruit RGB Negative 16x2 LCD+Keypad Kit for my Raspberry Pi. When it is connected my pi will not power on and no status lights are displayed. Without the board connected everything is fine powers up correctly can be accessed by SSH etc. I suspect a short but cannot see any touching solder and nothing protrudes far enough to touch anything apart from the rubber foot that is supposed to rest on the ethernet connector. I'm somewhat at a loss any ideas/suggestions?