chore(package): update jest to version 22.1.1

Closes #15

Author: greenkeeper[bot]

package.json

@@ -48,7 +48,7 @@
     "eslint-plugin-standard": "3.0.1",
     "eslint-plugin-xss": "0.1.8",
     "fixpack": "2.3.1",
-    "jest": "21.2.1",
+    "jest": "22.1.1",
     "jest-cli": "21.2.1",
     "markdown-magic": "0.1.19",
     "markdown-magic-dependency-table": "1.3.2",