Add Renard support to FPP UI and FPPD code.

(cherry picked from commit 5e55d297586ac59d9476e061017d5829d212b40b)

This commit also converts the Renard code to use the new Channel Output
configuration method rather than usbdongle.php which will be removed
shortly.

Code is currently untested as I have no Renard equipment.

Conflicts:
	src/channeloutput/channeloutput.c
	www/usbdongle.php