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Dec 8, 2017

- More buttons!
- Adding 'undo stroke' button on main drawing page. The back button can also do the same thing, but new button is visible on-screen.
- Adding 'grade override' button - when sure you drew correctly, you can override the grading system.
- Fix bug in landscape tablet layouts, where the study button after an incorrect draw could be unclickable.
- Fix bug introduced with SRS, where character progression could be shuffled, even if option not set.