More robot stuff, start in on path planning and cleanup rmcd a bit.

	* robots/emc/emcd.c: Update for obstacle-related changes in mtp.

	* robots/mtp/mtp.x, robots/mtp/mtp.h, robots/mtp/mtp.c,
	robots/mtp/mtp_send.c: Add messages for requesting/reporting robot
	sensor contacts, plus some cosmetic changes to the obstacle_config
	structure.

	* robots/primotion/garcia-pilot.cc,
	robots/primotion/pilotClient.hh, robots/primotion/pilotClient.cc:
	Add support for sending "contact" reports, which contain points
	where the sensors have detected an object.

	* robots/rmcd/GNUmakefile.in, robots/rmcd/obstacles.h,
	robots/rmcd/obstacles.c, robots/rmcd/pilotConnection.h,
	robots/rmcd/pilotConnection.c, robots/rmcd/rclip.h,
	robots/rmcd/rclip.c, robots/rmcd/rmcd.c: Cleanup and add in some
	obstacle avoidance.