Update autorship of latest Milkytracker and OpenMPT

From Johannes Schultz:

 By the way, the latest MilkyTracker release in your graph should be
 attributed to Deltafire, pailes hasn't worked on it. Also, all of the
 OpenMPT 1.22 releases should be attributed to Saga Musix & manx, since
 he did a tremendous amount of work on it as well.

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>