💥 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/rest/config.el

@@ -1,6 +1,6 @@
 ;;; lang/rest/config.el -*- lexical-binding: t; -*-
 
-(def-package! restclient
+(use-package! restclient
   :mode ("\\.http\\'" . restclient-mode)
   :config
   (set-popup-rule! "^\\*HTTP Response" :size 0.4 :quit 'other)
@@ -30,7 +30,7 @@
         "c" #'restclient-copy-curl-command))
 
 
-(def-package! company-restclient
+(use-package! company-restclient
   :when (featurep! :completion company)
   :after restclient
   :config (set-company-backend! 'restclient-mode 'company-restclient))