simplify transpose method

This is kind of what I am thinking:
remove doubles, and half step enharmonics like E# and Fb etc... no one cares.... probably

convert the incoming chord root into an integer
do math
convert is back to a note name and chose enharmonic base on a flat key array

for the most part, this takes care of things... by if you transpose into a weird key you could end up with an Fm7 chord in the key of Gb... but I don't think that's a big deal.

The diff is really strange, so you may want to merge this into a branch in your repo to better see how the code flows.  I did leave it hooked up to your processChord method.

Overall... I'm blown away by your first attempt.  Great job!