Feature changes:
- Improve term export: export all terms, change headings to be immediately importable.
- Add hotkeys to reading menu (pulled from manual).
Bugfixes:
- Fix sentences link.
- Fix spelling of "dismiss" in anchor tag for remove_demo_flag
- Fix scrolling bug on update. By @webofpies.
- Fix z-index of player and popup. By @webofpies in #127.
Back end changes:
- Change tagging library to tagify