Merge pull request #259 from shower/greenkeeper-shower-core-2.0.6

shower-core@2.0.6 untested ⚠️

package.json

@@ -27,7 +27,7 @@
     "README.md"
   ],
   "dependencies": {
-    "shower-core": "^2.0.5",
+    "shower-core": "^2.0.6",
     "shower-material": "^1.0.4",
     "shower-ribbon": "^2.0.4"
   },