Japanese v1.86

A minor maintenance update:

[Added] Loop the kanji animation setting (study settings)
[Changed] Increased difficulty of "normal" and "hero" levels
[Changed] Removed v1.83 bug code (study settings)
[Changed] Keyboard pops up in new file view
[Fixed] Progress bar in study view rotation bug
[Fixed] Switches in study settings now remember their positions correctly

Other minor changes

Available in a few days.