chore(package): update rollup to version 2.10.3

Closes #28

Author: greenkeeper[bot]

package.json

@@ -62,7 +62,7 @@
     "husky": "^3.0.8",
     "jest": "^24.9.0",
     "nyc": "^14.1.1",
-    "rollup": "^1.23.1",
+    "rollup": "^2.10.3",
     "rollup-plugin-babel": "^4.3.3",
     "rollup-plugin-commonjs": "^10.1.0",
     "rollup-plugin-includepaths": "^0.2.3",