Fix that +indexString warning.

Signed-off-by: Aron Cedercrantz <aron@cedercrantz.se>
Turn on a bunch of warnings.

- Will make it easier to find issues and fix them.
- See next commit for fixes of the issues triggered by these warnings.

Signed-off-by: Aron Cedercrantz <aron@cedercrantz.se>
Fix all the new warnings triggered by newly turned on warnings.

- See previous commit (1cb847c623e9ce4504895fc78fcb0d980b46a46a) for the
warning flags.

Signed-off-by: Aron Cedercrantz <aron@cedercrantz.se>
Merge branch 'master' into feature/styling

* master:
  Fix all the new warnings triggered by newly turned on warnings.
  Turn on a bunch of warnings.
  Fix that +indexString warning.