value entry for temperament NoiseUser

[tjingboem]

i need help in setting a value for the new temperament NoiseUser.

I added this NoiseUser temperament by copying NoiseHeavy and added the name NoiseUser and abbreviations to temperamentNames (line 259 and line 277 in temperament.py).
It is already part of the latest alpha version.

In line 247 i gave a fixed value : maxNoise = 10
but it would be much better if the user could enter a value 0 - 100.

The NoiseUser temperament can then deviate from the given pitch or frequencies as given by the user.
NoiseLight, Medium and Heavy are based on this but are add the deviation (noise) with fixed values of .05, 0.10 and 0.15.

NoiseUser would be able to set the value deviation 0 -100% from given pitch or frequencies.