chore(package): update steal-tools to version 2.1.0

Closes #285

Author: greenkeeper[bot]

package.json

@@ -76,7 +76,7 @@
     "jshint": "^2.9.1",
     "steal": "^1.0.0",
     "steal-qunit": "^1.0.0",
-    "steal-tools": "^1.0.1",
+    "steal-tools": "^2.1.0",
     "testee": "^0.8.0"
   }
 }