Clamp01 needed for Whittaker inputs

passing in a value OUTSIDE of Mathf.Clamp01 range to the input of a Whittaker graph and the threads will all fail

(since, I am guessing, internally you do some kind of partitioning to get an index from that - and this is not guarded against non-normalised input.)

EXPECTED RESULT : I suppose people would expect it to (Math.Clamp01(TheStupidValue)) internally.

ACTUAL RESULT: Threads fail with 'index' errors

TO FIX: Simply add a test for Clamp01 to the Temperature and Moisture graph inputs.