New JSX language under JavaScript group

A specific grammar is needed to highlight .jsx files
Thus, there are now in a distinct language but still in the JavaScript group

lib/linguist/languages.yml

@@ -1575,6 +1575,14 @@ JSONiq:
   - .jq
   tm_scope: source.jq
 
+JSX:
+  type: programming
+  group: JavaScript
+  extensions:
+  - .jsx
+  tm_scope: source.js.jsx
+  ace_mode: javascript
+
 Jade:
   group: HTML
   type: markup
@@ -1628,7 +1636,6 @@ JavaScript:
   - .jsfl
   - .jsm
   - .jss
-  - .jsx
   - .njs
   - .pac
   - .sjs