Fix QSettings problems:
- Reopen file in ReadOnly mode if it was open in ReadWrite mode
and is being read. This is needed for stupid QSettings which
opens file in ReadWrite mode just to call readAll() on it.
- Implement setSize(0)
Google Code-in: Center help text field
Modifies the grid layout slightly so that the help text which appears when hovering over certain elements is centered with respect to the window, even when there are more buttons on one side.
https://google-melange.appspot.com/gci/task/view/google/gci2012/7968226