# 6.6.0.0
- Import Bibutils 6.6.
- Expose NBIB output support.
# 6.5.0.0
- Import Bibutils 6.5.
# 6.4.0.0
- Import Bibutils 6.4.
# 6.3.0.1
- Fix MacOS X compilation.
# 6.3.0.0
- Update to Bibutils 6.3.
- Enable NBIB support.
- Expose additional options values.
# 6.2.0.1
- This is a patch release fixing MacOS X compilation.
- Patched few minor warnings in imported Bibutils source.
- Implemented Travis-CI builds through Cabal and Stack.
# 6.2
- This release has removed `wordout_dropkey` because the corresponding
constant in Bibutils has also been removed.