* Set x-kde-urls for notifications
The x-kde-urls field in the hints map allows us to provide a direct URL
to the saved screenshot. The notification server may then use this hint
to provide extra functionality, such as drag and drop support and
thumbnails.
For more information see https://community.kde.org/Plasma/Notifications#File_PathFixes#256
Note that other notification servers may ignore this hint.
* Avoid branching twice for ok
More flexible tool API
Minor code format fixes
Clipboard freeze fixed(?)
Arrow correcly growing close to the start point
Improve maintainability
Add undo/redo stack
-use of the override keyword
-delete unused code
-const correctness
-more uniform code style
-for each with const references when possible
-getters no longer use the word 'get'
-others
