Half-should-be-working implementation of syncing
Finish and clean up the client sync code
Move back to Qt4, add Plasma dataengine and plasmoid

The Daemon is still built with Qt5, for integrated QJson. The DBus-wrapper QtLib and all the rest uses Qt4 and KDE4. DataEngine provides a list of projects, but it's probably better to expose the QtLib objects to QML for better flexibility.