chore(package): update webpack peerDependencies

Author: joshwiens

package.json

@@ -28,7 +28,7 @@
     "url": "https://github.com/webpack/karma-webpack.git"
   },
   "peerDependencies": {
-    "webpack": "^1.1.0 || ^2 || ^2.1.0-beta || ^2.2.0-rc"
+    "webpack": "^1.1.0 || ^2 || ^2.1.0-beta.0 || ^2.2.0-rc.0"
   },
   "dependencies": {
     "async": "~0.9.0",