T-junctions.

use them.  Also fixed the "on" state image for wire ends so that it works for
curved wires also.

cause too many new ones.

now the insulated wires change their color when are turned on

The node property is_sticky_piston was applied to piston_up_normal rather than piston_up_sticky.

Conflicts:
	mesecons/internal.lua
	mesecons/wires.lua
	mesecons_pistons/init.lua

Add rule-name system. Every input rule can now have a name, that could help e.g. the microcontroller to know where a signal comes from.