bake_route fixes

[DasCapschen]

Sometimes, bake_route() would not detect rails that should be connected.
Example:

currentrot = -180
rail.startrot = 179.999985
Math.normDeg(currentrot) = 180
Math.normDeg(rail.startrot) = 539.999985
abs(Math.normDeg(currentrot) - abs(Math.normDeg(rail.startrot))): 359.999985

The expected distance is 0.000015, because 180 and -180 are infact the same angle. But this was handled incorrectly.