Set character encoding when saving JSON.
Suggest file name for competition JSON. Make UI labels more descriptive and consistent.
Merge pull request #85 from jfly/master

If all the cells are filled in on a combined round, complain! fixes #40.
Validation errors related to the round should be reported as such. #40
Added drag and drop support for scramble files. #76
Have one common working directory for all file choosers. #87
Move generate SQL buttons behind Advanced button. #88
Clean up code. #88