Initial commit

- App downloads json file, parses it and shows list of categories on first
  screen
- search support
- bar code scan support
- bar code compare and recognition
- shows message if item is allowed to buy
Disabled qr scanning
Changed Theme
Added loading indicator
Error handling in case if there is no internet
Added lint file
Added scanner library
Merge branch 'master' of https://github.com/khartash/dememscanner