launcher: Properly quit if settings write fails.
launcher: Throw error if no data files are selected
launcher: Instead of killing config writing due to no master files being selected, instead display a warning when Play is pressed.
Merge remote-tracking branch 'darkf/issue-812'
updated credits file
better const correctness for MwIniImporter
no const for int and bool
Bugfix #809
Merge remote-tracking branch 'glorf/bugfix2'