D15645: Add scheme selection menu with a "System" entry.

[Nathaniel Graham]

ngraham added reviewers: broulik, cfeck, elvisangelaccio.

REPOSITORY
  R265 KConfigWidgets

REVISION DETAIL
  https://phabricator.kde.org/D15645

To: amhndu, #frameworks, broulik, cfeck, elvisangelaccio
Cc: ngraham, broulik, kde-frameworks-devel, michaelh, bruns