F5 keyboard shortcut to reload / refresh the current branch or tree
Pressing F5 should reload the view just like clicking that toolbar button.
Ideally, this should be based on a rebased version of @cheywood's !25 (for #12) so that the F5
key scans only the currently selected folder, and Ctrl+F5 (or Shift+F5?) rescans the whole tree (I think this shouldn't be the main shortcut instead of rescanning only the selected branch, because rescanning the whole tree has bigger performance implications?).