Rewrite workspace KCM in QtQuick
This patch renews the System Settings -> Desktop Behaviour -> Workspace.
Basically it is rewritten in QML, ConfigModule. Also, its naming has been
changed. It was called as kcm_workspaceoptions and workspaceoptions before
but now, it is kcm_workspace like other renewed KCMs' names.
Currently, ToolTip and VisualFeedback working fine. All the functionalities
are tested. "Default", "Reset" buttons works like a charm.
Reviewers: romangg, ngraham, Plasma
Reviewed By: romangg, Plasma
Subscribers: zzag, davidedmundson, plasma-devel
Differential Revision: https://phabricator.kde.org/D12936