Add cut,copy and paste functionality.

lua/lib/config.lua

@@ -54,6 +54,9 @@ function M.get_bindings()
     create      = keybindings.create or 'a',
     remove      = keybindings.remove or 'd',
     rename      = keybindings.rename or 'r',
+    cut         = keybindings.cut or 'x',
+    copy        = keybindings.copy or 'c',
+    paste       = keybindings.paste or 'p',
   }
 end