Log Message:
fasttracker2: update to b160

Changes since b159

Beta #160 - 19.06.2019
- Bugfix: Certain instrument properties could be modified even if the current
  instrument was zero. This is a special ins. number for pattern editing, it's
  not a real instrument. (You can set ins. #0 by pressing 0 on the numpad).
- Bugfix: It was impossible to select an instrument higher than 0x60 (100) when
  using the numpad keys.
- Bugfix: "Srnk." (shrink pattern) would erase the last row after its \ 
operation
- Bugfix: When loading a floating point .wav, it would only load silence unless
  the amplitude peaked at max (1.0).
- Bugfix: 16-bit mono .aiff files would not load correctly at all!
- When loading 24-bit .wav/.aiff files, properly normalize amplitude before
  converting to 16-bit. This now takes up more CPU time and RAM, but it's worth
  it.
- Default instrument envelopes were always read from preset slot #1. I don't
  like this at all, as it could mess things up when loading sample-only songs.
  It has now been changed to always use the stock envelope values when loading
  such files or when a new project is started (or instruments zapped).
- Properly reject .it (Impulse Tracker) modules when attempted to be loaded
- Code cleanup. Proper space alignment for special tab indents, removed
  extreme use of parenthesis, spaces etc.