Setting level or pan/balance of LR in a matrix almost certainly doesn't work

[jswalden]

Going from code inspection, just as assigning LR to matrixes doesn't work (#34) because the parameter calculations mishandle LR being encoded as 99, I'm about 99% confident that changing pan/balance or level of LR within a matrix is broken for the same reason.

While I have a fix for LR-to-matrix assignment (gated behind various refactorings landing), I don't have one for these yet. setLevel and fadeLevel are two of the few stalls of this module's Augean stables that I haven't yet managed to clean up yet to the point where the code is intelligible to me. I might be able to fix the problem using techniques similar to what I used in #34, without having to understand them first, but I'm not sure.

[jswalden]

I believe this is fixed as of 2578dc1 -- the point at which a final switch was made from the old busted fade-to-level implementation to a new one, invoked by different callers that correctly handle LR as source distinct from mixes as source.

No promises when a release with the fix will be made. I'm down to very, very little remaining cleanup left, tho, so it's somewhat likely "sooner" rather than later.