Updated Slovenian translation - thx Hawk :)
Updated change log
Update AppVeyor config.
Improve Matroska files processing
Merge pull request #294 from SubtitleEdit/matroska

Improve Matroska file handling
Optimize batch convert threading
Merge pull request #293 from SubtitleEdit/batch_convert

Improve batch convert threading
Convert some delegates to lambdas
nl-NL translation: minor corrections/improvements + new tags
nl-NL translation: spcorr + experiment (buttons)
nl-NL translation: preferences 1