chore(package): update axios to version 0.19.1

Closes #32

Author: greenkeeper[bot]

package.json

@@ -20,7 +20,7 @@
     "@babel/node": "^7.0.0",
     "@babel/preset-env": "^7.1.6",
     "@babel/register": "^7.0.0",
-    "axios": "^0.18.0",
+    "axios": "^0.19.1",
     "chai": "^4.2.0",
     "mocha": "^5.2.0",
     "nodemon": "^1.18.7",