Added runcommandplugin widget
Summary: A simple widget to execute commands from android desktop
Add the widget and execute commands from it.
By default, the selected device is the first device in the device list.
The selected device can be changed via the widget title.
If there is no commands, the widget show an empty list
If there is no connected device, show the message located in @string/unreachable_description
Reviewers: albertvaka, nicolasfella, KDE Connect
Reviewed By: albertvaka
Subscribers: kdeconnect, nicolasfella
Tags: KDE Connect
Differential Revision: https://phabricator.kde.org/D12507