Add Clojure. (#50)

Author: slabruyere

src/renderer/assets/data/languages.json

@@ -3,6 +3,10 @@
     "name": "text",
     "extension": "txt"
   },
+  {
+    "name": "clojure",
+    "extension": "clj"
+  },
   {
     "name": "csharp",
     "extension": "csharp"

src/renderer/main.js

@@ -39,6 +39,7 @@ require('brace/mode/swift');
 require('brace/mode/typescript');
 require('brace/mode/xml');
 require('brace/mode/csharp');
+require('brace/mode/clojure');
 require('brace/mode/liquid');
 require('brace/theme/monokai');