Add lang/factor module (#2129)

Factor is a stack based programming language with an awesome emacs mode.

* remove extra layer of nesting for keybinds
* use-package!
* lazy load fuel
* fue listener typo
* remove extra space
* Add README

modules/lang/factor/config.el

@@ -0,0 +1,47 @@
+;;; lang/factor/config.el -*- lexical-binding: t; -*-
+
+(use-package! fuel-mode
+  :defer t
+  :init
+  (set-eval-handler! 'factor-mode #'fuel-eval-region)
+  (set-repl-handler! 'factor-mode #'run-factor)
+  :config
+  (set-lookup-handlers! 'factor-mode
+    :definition #'fuel-edit-word-at-point
+    :references #'fuel-show-callers
+    :documentation #'fuel-help))
+
+(map! :after factor-mode
+      :map factor-mode-map
+      :localleader
+      "t" #'fuel-test-vocab
+      (:prefix ("e" . "eval")
+        "d" #'fuel-eval-definition
+        "R" #'fuel-eval-extended-region
+        "r" #'fuel-eval-region)
+      (:prefix ("h" . "help")
+        "p" #'fuel-apropos
+        "v" #'fuel-show-file-words
+        "c" #'fuel-show-callees
+        "e" #'fuel-stack-effect-region)
+      (:prefix ("s" . "scaffold")
+        "v" #'fuel-scaffold-vocab
+        "h" #'fuel-scaffold-help
+        "t" #'fuel-scaffold-tests)
+      (:prefix ("r" . "refactor")
+        "s" #'fuel-refactor-extract-sexp
+        "w" #'fuel-refactor-extract-region
+        "v" #'fuel-refactor-extract-vocab
+        "i" #'fuel-refactor-inline-word
+        "g" #'fuel-refactor-make-generic
+        "u" #'fuel-update-usings
+        "r" #'fuel-refactor-rename-word))
+
+(map! :after fuel-listener
+      :map fuel-listener-mode-map
+      :localleader
+      "e" #'fuel-edit-vocabulary
+      "r" #'fuel-refresh-all
+      "i" #'fuel-stack-mode
+      "h" #'fuel-help
+      "s" #'fuel-scaffold-vocab)