Updates for the Raspnerry Pi Compute Module - changes to the gpio program

Updates for the Raspnerry Pi Compute Module - changes to the gpio program
to produce a nicer 'readall' output too.

It also understands new pins 53,54,55 and 56 in wiringPiSetupPhys()
mode to represent the pins on the P5 connector on the Rev 2 Pi's

Changes to pinMode() to allow new modes SOFT_PWM and SOFT_TONE.