Assistant Performer now works on Mac Computers

Uploaded a new version of the Assistant Performer.
This version now uses Chris Wilson's Web MIDI API Polyfill, and fixes several bugs which prevented the program from running on Mac computers.
I am still only really testing this program in Chrome on 64 bit Windows 7, but have high hopes that it will soon be running on all other major browsers/systems.

Updated the file About the Assistant Performer