#7 Easier ways to change mark

[Steiner]

It would be nice to have quicker ways of changing the mark on a class. Having to right click - locate correct mark - left click is too tedious if you have many classes in focus.
Adding keyboard shortcuts (one for each mark) and/or small buttons in the table would be a great start. If possible, please consider multi-change, i.e. if I select 5 classes and choose a mark, this should be applied to all 5.