add some stuff.

change the pcb to satisfy minimum clearance of 5 mil

update openquadcopter.

Add holes as a pendant.

Change the PWM's TIM. (Do not use TIM1 for pwm, since the pins are also related to SPI pins)

wrap up openquadcopter board.

add xbee battery board, openquadcopter's schematic and pcb file.

change the footprint of capacity larger than 1uF to 0603 footprint. Update 3D sketchUp model

Add a picture for quadcopter

update sketchup model