Added some functions for I2C communication.
PICrouter firmware v1.5.10 release.

Supported to control I2C with OSC.
* The latest version is only supported a master send/receive.
Recompiled.
Merge branch 'master' of https://github.com/tkrworks/PICrouter
Merge branch 'master' of https://github.com/tkrworks/PICrouter