Fix 3 bugs: #964, #967, and that persistent cross-platform script permissions bug after unzipping
Merge branch 'release-0.11' of github.com:learningequality/ka-lite into 964_967
fixing inverted subtraction for shifting
Merge pull request #1024 from bcipolli/964_967

Fix 3 bugs: #964, #967, and that persistent cross-platform script permissions bug after unzipping