Peg sinon to 1.10.2 to work around bug

1.10.3 has an issue with fake XHRs. Don't update until https://github.com/cjohansen/Sinon.JS/issues/511 is fixed.

@@ -33,7 +33,7 @@
     "karma-qunit": "~0.1.1",
     "karma-safari-launcher": "~0.1.1",
     "karma-sauce-launcher": "~0.1.8",
-    "sinon": "^1.9.1",
+    "sinon": "1.10.2",
     "video.js": "git+https://github.com/dmlap/video-js.git#0.6.1-alpha"
   },
   "dependencies": {