Allow webpack 2 RC (#160)

Author: bondz

package.json

@@ -4,7 +4,7 @@
   "author": "Tobias Koppers @sokra",
   "description": "Offers a dev middleware for webpack, which arguments a live bundle to a directory",
   "peerDependencies": {
-    "webpack": "1 || ^2.1.0-beta"
+    "webpack": "1 || ^2.1.0-beta || ^2.2.0-rc.0"
   },
   "dependencies": {
     "memory-fs": "~0.4.1",