Simplify UnitconvEng and CalcEng

Now over generates a bit because considers "in" and "to" equivalent, e.g.

	please convert X in Y
	how much is X to Y

ActionEng FSG size was reduced from 20k -> 13k.

Also, the first variant is now the shortest form, and is used for TTS.

Also, "what" is variant for "how much".