Display keys with Command modifiers correctly

On my system, I was noticed that keys I would press with command characters (command, shift, option, control) would all display as 

(COMMAND_KEY)^A(KEY)

I dug into the code to figure out where ^A was coming from, and it didn't seem to be inserted anywhere in the transformer, so the best I can tell is that they are being created with the control character ^A in them.

Also took some time to inspect the other forks of keycastr and was very surprised no one else has fixed this yet. There's an issue on the original (https://github.com/sdeken/keycastr/issues/6) that describes the same behavior I saw, but no one has responded. 

Anyway, I hope this is helpful, it certainly was for me!