Add support for sharing text from plasmoid
Summary:
This allows you to enter text in the plasmoid and it be sent
to the connected device.
Reviewers: VDG, KDE Connect, albertvaka
Reviewed By: KDE Connect, albertvaka
Subscribers: apol, kdeconnect
Tags: KDE Connect
Differential Revision: https://phabricator.kde.org/D16696