Refactor out map.el usage

After some profiling, it turns out map-put and map-delete are 5-7x
slower (more on Emacs 25) than delq, setf/alist-get and add-to-list for
small lists (under 250 items), which is exactly how I've been using
them.

The only caveat is alist-get's signature is different on Emacs 25, thus
a polyfill is necessary in core-lib.

modules/ui/popup/config.el

@@ -70,8 +70,8 @@ adjustment.")
                window--sides-inhibit-check nil)
          (+popup|cleanup-rules)
          (dolist (prop +popup-window-parameters)
-           (setq window-persistent-parameters
-                 (map-delete window-persistent-parameters prop))))))
+           (delq (assq prop window-persistent-parameters)
+                 window-persistent-parameters)))))
 
 (define-minor-mode +popup-buffer-mode
   "Minor mode for individual popup windows.