Remove unused core files

core/core-set.el

@@ -1,23 +0,0 @@
-;;; core-set.el --- centralized inter-package configuration
-
-(defvar doom-settings '()
-  "docstring")
-
-(defun doom-define-setting (name &optional docs &rest args)
-  (declare (indent defun)))
-
-(defun doom-set (mode key value)
-  (declare (indent defun)))
-
-(defmacro config! (package-name &rest args)
-  (declare (indent defun))
-  `(let ((doom-current-package ',package-name))
-     ,(macroexpand-progn args))
-  ;; 1. Check for `set!' calls
-  ;; 2. Append mode
-  )
-
-(defmacro set! (&rest args))
-
-(provide 'core-set)
-;;; core-set.el ends here