Adds control-v binding that copies it to the clipboard.
THIS ONLY WORKS WITH CLIPBOARD MANAGER!!! once rofi is closes, the data is
gone!
This needs to be tested. Documentation on this is lacking so reversed
engineered from other applications.
TODO: how do we do the SAVE_TARGETS?
fixes: #378
* [Listview] Initial implementation for left to right packing.
* [Listview] fix movement in pack-left-to-right.
* Add element-next/prev keybinding and remap tab.
* [Listview] Change option name to 'flow' and use rofi orientation type.
* [Listview] Make listview work with reverse property.
* Update test for 2 new keybindings.
fixes: #1058
