Define display-4k-vertical

I recently acquired a new monitor, which I'm orienting vertically for logs,
chats, etc. As such I needed to add more functions, KBDs to wrangle the
setup. To DRY up my code, I define a macro, `display-register`, as a DSL for
supporting new monitors. This:
- defines two functions for enabling and disabling the displays
- defines a constant, `display-<name>`

It's basically just a wrapper around `xrandr`, and that's good enough for now.

emacs/.emacs.d/wpc/keybindings.el

@@ -224,14 +224,15 @@
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (when (device-work-laptop?)
-  (keybindings-exwm "<XF86Display>" #'display-cycle-display-states)
   (general-define-key
    :prefix "<SPC>"
    :states '(normal)
-   "d0" #'display-disable-laptop
-   "d1" #'display-enable-laptop
-   "D0" #'display-disable-4k
-   "D1" #'display-enable-4k))
+   "d0" #'display-enable-laptop
+   "D0" #'display-disable-laptop
+   "d1" #'display-enable-4k-horizontal
+   "D1" #'display-disable-4k-horizontal
+   "d2" #'display-enable-4k-vertical
+   "D2" #'display-disable-4k-vertical))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; notmuch