Add trailing slash to docs URLs incase GitHub gets confused.
Add the start of a more in-depth platforms section of docs.
Re-organize platform-specific docs to be more centralized.

Fixed #103.
Document process for supporting multiple archs and variants.

Fixed #109.
Point to new OpenXC message format repo.
Remove UART compiler flag in favor of reading status from GPIO.

Fixed #111.
Fix serial status check on chipKIT - use analog to not require pull-up.
Merge branch '111-nouartflag' into v4.0

Conflicts:
	CHANGELOG.mkd
	docs/installation/compiling.rst
	docs/output/uart.rst
	src/Makefile
	src/interface/uart.h
	src/main.cpp
	src/pic32/bluetooth.c
	src/platform/lpc17xx/bluetooth.cpp
	src/platform/lpc17xx/serialutil.cpp
	src/platform/pic32/serialutil.cpp
	src/tests/bluetooth_mock.c
	src/tests/serialutil_mock.cpp
	src/tests/tests.mk
Stop handlers.h/cpp from interfering with unit tests.
Rename platform implementation files to match headers.
Re-bump arduino.mk, test suite passing again.