Log Message:
fasttracker2: update to b147

Changes since b142:

Beta #147 - 08.04.2019
- Fixed a bug from beta #146 where the sample playback line in Smp. Ed. could
  wrongly be rendered if you switched samples after using the
  "Play Wave/Range/Display" function.
- Updated some of the help text in "Known bugs"

Beta #146 - 02.04.2019
- Fixed a bug where you couldn't select envelope points appropriately
  (bug present since beta #140).
- Fixed a problem where the pattern data scrolling would start to stutter more
  if you left the song playing for a minute or so.
- Fixed a problem that made the scopes slightly delayed to the music. Most
  people won't notice a difference, though.
- Fixed a scope bug where it could display one frame of bogus data before a
  new sample trigger.
- More fixes to .MOD/.STM/.S3M import
- Made some changes to the help text
  ("How to use FT2", "Problems/FAQ", "Known bugs").

Beta #145 - 31.03.2019
- Fixed some bugs in the .MOD saving routine
- Slightly improved the .STM loader

Beta #144 - 30.03.2019 (updated 30.03.2019)
- Further fixing to prevent more possible stutter with vsync (60Hz monitor)
  on some monitors (rare case).
>> 30.03.2019:
- Sometimes the mouse would be off center when toggling fullscreen mode
- Forgot to round when doing mouse scaling
- 1.5-bit dithering wasn't implemented properly

Beta #143 - 29.03.2019
- Scopes have been lowered from 60Hz to 55Hz to prevent random stutters
  on some systems because of timing interference. If your monitor is not
  running at 59Hz/60Hz, they will stutter anyways.
- Fixed a bug where the pattern delay (EEx) effect was not reset every time you
  press Play.