Modal Window - rebound

Changes made:

* Checkmarks are now checkboxes
* Text neatly aligned
* Header font (Instellingen) now changed to Open Sans, in accordance with the rest of the fonts. Might change the header font again, though.
* Text shadow removed
* "« Golf" is now "‹ Golf", indicating it only goes up 1 level, as apposed to two.
* Bottom nav bar now also has a flat (gradientless) appearance, like the rest of the app.