Use mBot original firmware and protocol

[paulolc]

In order to solve #4 and #3, the only way is to move away from standard firmata since it doesn't support buzzer with bluetooth and the IR receiver. The mBot original firmware supports everything.

References:

mbot_firmware.ino

mBlock mBot blocks definition

mBot.s2e
mBot source @mBlock
MeUltrasonic.cpp
mbot.js
How to add and extention for mBlock