Keys.podspec.json in cocoapods-keys-1.2.1

- old
+ new

@@ -15,9 +15,9 @@
   },
   "source": {
     "git": "https://github.com/orta/cocoapods-keys.git",
     "tag": "23"
   },
-  "source_files": "*",
+  "source_files": "*.{h,m,swift}",
   "frameworks": "Foundation",
   "requires_arc": true
 }
\ No newline at end of file