feat: resurrect prefer-arrow-callback

it's --fix'able, which helps when decaf'ing code

examples/eslint/node4/prefer-arrow-callback.js

@@ -0,0 +1,21 @@
+'use strict';
+
+function a() {}
+
+// uncomplicated callback: use arrow
+const b = a().then(() => {
+  const c = 42;
+  return c;
+});
+
+// uses this?  use function
+const d = a().then(function() {
+  this.stuff();
+});
+
+// uses arguments?  use function
+const e = a().then(function() {
+  return arguments;
+});
+
+module.exports = [b, d, e];

lib/rules/conventions.js

@@ -71,4 +71,7 @@ module.exports = {
 
   // See: https://eslint.org/docs/rules/prefer-template
   'prefer-template': 'error',
+
+  // See: https://eslint.org/docs/rules/prefer-arrow-callback
+  'prefer-arrow-callback': 'error',
 };