Require WinAVR's avrdude in Cygwin - MPIDE version missing a library.
Bump Arduino.mk for improved avrdude support in Cygwin.
Use com3 by default in Windows (first available COM port).
Make Cygwin dll executable, and then avrdude from MPIDE works in Windows.
Add quickstart guide for compiling from source.
Set default VCP in Cygwin.
Merge branch 'next' into windows-avrdude

Conflicts:
	upload_hex.sh
Merge branch 'next' into windows-avrdude
Merge branch 'next' into windows-avrdude

Conflicts:
	docs/installation/binary.rst
	src/pic32/pic32.mk