Use Ctrl+D as keyboard shortcut to remove albums or files

https://community.metabrainz.org/t/add-remove-shortcut/460545?u=zas

The main issue here is not to add the Ctrl+D shortcut, but rather re-allocate it because it is currently used by Add Folder action.
What I suggest:
Use `Ctrl+E` as keyboard shortcut and `e` as accelerator for Open Folder
Use classsic QKeySequence.Delete for remove action (depending on platform: Del/Ctrl+D/Meta+D)

https://doc.qt.io/qt-5/qkeysequence.html