ace-window.el: remove aw-generic macro

* ace-window.el (aw--current-op): New var.
  (aw--callback): New command, replaces "...-wrapper" from `aw-generic'.
  (aw--doit): New function, replaces the other part of `aw-generic'.
  (ace-select-window): Update.
  (ace-delete-window): Update.
  (ace-swap-window): Update.
  (aw-switch-to-window): Now expects only an aj-data structure.
  (aw-delete-window): Now expects only an aj-data structure. Will
  `delete-frame' when there's only one window if frame.
  (aw-swap-window): Now expects only an aj-data structure.