Pipe standardization

Cleaned up pipes.dm
Changed pipe subtypes to the following layout:
	pipe
		simple/manifold/manifold4w
			hidden
				colour
			visible
				colour

Did a complete pass of the station to standardize all pipes (yes, nearly 2500 changes)
(Haven't done the research base air and scrubber pipes yet, and atmos will be done with my engineering redesign)
Merge pull request #4385 from Loganbacca/pipes-cleanup

Pipe standardization