revamped pumps so that now they should sit in/on liquid and be connected only
from the top, relegated grates to decorational-only, added outlet spigot.  Got
rid of a few obsolete textures.  Got rid of that whole _x and _z naming thing,
now all directional devices (pumps, valves, spigots, tanks) use facedir.
Valves, spigots no longer auto-rotate to find nearby pipes.