Feature to move up file hierarchy with Alt+Up

From: https://en.wikipedia.org/wiki/Table_of_keyboard_shortcuts#Browsers_/_Go_menu

Alt+Up moves up the file hierarchy until it hits root.
So, if "/home/josh" is opened, Alt+Up would move to "/home"

src/key_bind.rs

@@ -57,6 +57,7 @@ pub fn key_binds() -> HashMap<KeyBind, Action> {
     bind!([Ctrl], X, Cut);
     bind!([Alt], Right, HistoryNext);
     bind!([Alt], Left, HistoryPrevious);
+    bind!([Alt], Up, LocationUp);
     bind!([Ctrl], V, Paste);
     bind!([Ctrl], A, SelectAll);
     bind!([Ctrl], W, TabClose);