audio/fasttracker2: Update to v1.04

- MASTER_SITES has been updated to Github since the author has moved to the
  source there.

Changes since v1.03:

v1.04 - 17.12.2019
- Fixed rare crash (or strange behaviors) when changing pattern and/or pattern
  length while the song is playing.
- Properly restore channel mute flags when loading a new song (fixes mute bugs)
- Fixed a few bugs with different pattern buttons (Ins./Del., Ln. up/down etc)
- Config: "Hardware mouse" was changed to "Software mouse" (and "Software mouse"
  is now disabled in the default config).
- Added a routine to create scaled FT2 mouse cursors for software mouse mode,
  though the "busy mouse" will stand still and not animate.
  Hopefully the new default "hardware mouse" mode will satisfy some people!
- MacOS: Pass NDEBUG to clang preprocessor defines, to prevent debug code
  from being compiled in release mode (performance increase).
- MacOS/Linux: make scripts had Windows linefeeds and would thus break!

* Note: I highly recommend that you go to "Config -> Layout" and disable
  "Software mouse"! This will make the mouse way less laggy. However, it will
  still be one frame delayed internally unless you disable VSync.


(fox)