Exaile 4.0.0-beta2 released

[Dustin Spicuzza]

This release comes highly recommended:

• Forces usage of bsddb/bsddb3 for the music database (to fix msys2 issues on Windows)
• Various minor fixes (https://github.com/exaile/exaile/compare/4.0.0-beta1...4.0.0-beta2 for details)
  

See https://github.com/exaile/exaile/releases for the latest releases. If you want to help fix the remaining issues for the 4.0 release, check out https://github.com/exaile/exaile/milestone/2