chore(package): update rollup to version 0.63.1

Closes #20

Author: greenkeeper[bot]

package.json

@@ -37,7 +37,7 @@
     "react": "^16.3.2",
     "react-dom": "^16.3.2",
     "react-test-renderer": "^16.3.2",
-    "rollup": "^0.59.1",
+    "rollup": "^0.63.1",
     "rollup-plugin-babel": "^3.0.4",
     "rollup-plugin-clear": "^2.0.7",
     "rollup-plugin-postcss": "^1.6.1",