Move printing to a new tools button
In order to gain more horizontal space, Export Image... is renamed
to Export, which is in line with the other buttons not repeating
"image". "..." is removed as it should be only added to the menu entries
itself if necessary and the arrow on the button is enough to indicate
- Printing via the button still works, as well as Ctrl+P.
- Somewhat sensible icon chosen for the button.
- Docbook updated.
Reviewers: Spectacle, ngraham
Reviewed By: Spectacle, ngraham
Differential Revision: https://phabricator.kde.org/D10371