Increased karma version.

socket.io made recent breaking changes to their internals that
older versions of karma uses (See karma-runner/karma#1782).

The old bug with newer karma versions has disappeared and is
assumed fixed (See 817ea3d).

Change-Id: Id1efa635de34f3d864c51c784b2343b8c9d9adee

package.json

@@ -12,7 +12,7 @@
   ],
   "devDependencies": {
     "in-publish": "",
-    "karma": ">=0.13.9 <= 0.13.14",
+    "karma": ">=0.13.19",
     "karma-coverage": "",
     "karma-jasmine": "",
     "karma-jasmine-ajax": "",