chore(tazjin/emacs): minor configuration cleanups

Deletes some stuff that I think isn't necessary anymore, and
consolidates the modes.el content into settings.el.

Change-Id: Ib682dbdb4eb89b3a7ee2eca89da4151af806a508
Reviewed-on: https://cl.tvl.fyi/c/depot/+/10187
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI

users/tazjin/emacs/config/functions.el

@@ -15,13 +15,13 @@
           (goto-line target)))
     (setq-local display-line-numbers nil)))
 
-;; These come from the emacs starter kit
-
 (defun esk-add-watchwords ()
   (font-lock-add-keywords
    nil '(("\\<\\(FIX\\(ME\\)?\\|TODO\\|DEBUG\\|HACK\\|REFACTOR\\|NOCOMMIT\\)"
           1 font-lock-warning-face t))))
 
+(add-hook 'prog-mode-hook 'esk-add-watchwords)
+
 (defun esk-sudo-edit (&optional arg)
   (interactive "p")
   (if (or arg (not buffer-file-name))