Update dependencies

Author: rdmurphy

package-lock.json

@@ -44,7 +44,7 @@
     "@babel/preset-typescript": "^7.3.3",
     "builtin-modules": "^3.1.0",
     "mri": "^1.1.4",
-    "rollup": "^1.19.4",
+    "rollup": "^1.20.1",
     "rollup-plugin-babel": "^4.3.3",
     "rollup-plugin-commonjs": "^10.0.2",
     "rollup-plugin-json": "^4.0.0",