fix(package): update fast-csv to version 4.1.5

Closes #55

Author: greenkeeper[bot]

package.json

@@ -40,7 +40,7 @@
     "cross-env": "^5.1.3",
     "d3-node": "^1.1.3",
     "debug": "^3.1.0",
-    "fast-csv": "^2.4.1",
+    "fast-csv": "^4.1.5",
     "fs-extra": "^6.0.1",
     "microtime": "^2.1.6",
     "mkdirp-promise": "^5.0.1",