chore(package): update sinon-chai to version 3.4.0

Closes #51

Author: greenkeeper[bot]

package.json

@@ -62,7 +62,7 @@
     "rimraf": "^2.5.2",
     "run-sequence": "^1.1.5",
     "sinon": "^1.17.4",
-    "sinon-chai": "^2.8.0",
+    "sinon-chai": "^3.4.0",
     "source-map-loader": "^0.1.5",
     "source-map-support": "^0.4.0",
     "ts-node": "^1.7.2",