💥 Rename def-package! -> use-package!

Calling this pivotal macro "def-package!" has frequently been a source
of confusion. It is a thin wrapper around use-package, and it should be
obvious that it is so. For this reason, and to match the naming
convention used with other convenience macros/wrappers, it is now
use-package!.

Also changes def-package-hook! -> use-package-hook!

The old macros are now marked obsolete and will be removed when straight
integration is merged.

modules/lang/purescript/config.el

@@ -9,13 +9,13 @@
     :documentation #'purescript-pursuit))
 
 
-;; (def-package! flycheck-purescript
+;; (use-package! flycheck-purescript
 ;;   :after purescript-mode
 ;;   :config
 ;;   (add-hook 'flycheck-mode-hook #'flycheck-purescript-setup))
 
 
-(def-package! psc-ide
+(use-package! psc-ide
   :hook (purescript-mode . psc-ide-mode)
   :config
   (remove-hook 'company-backends 'company-psc-ide-backend)