[Feature] Implement tab selection and multiple tab actions.

[matru]

Would be great if we could select multiple tabs, and do a few actions on them. At least closing, moving them with << or >>, even popping them out of the window, but the former two would be much more crucial.

Additionally it would be a great option if we could move even single tabs next to another tab (right in front can be the default) just by searching the destination tab with T as usual, and then pressing shift + Enter for example on it to bring the currently selected tab there. Of course this would be great if it could also work with multiple tabs.