Build: Add support for Arduino IDE 1.6.7

[mikaelpatel]

Release R1.1.1 does not work with latest Arduino IDE 1.6.7. The Arduino build fails due to pre-post build rules.

[mikaelpatel]

See commit 5fad31c. While waiting for R1.1.2 please use master (zip download and install) or simply replace the platform.txt with the pre-post build rules.

[mikaelpatel]

See commit 0b763a2