chore(package): update rollup to version 0.61.0 (#84)

Author: greenkeeper[bot]

package.json

@@ -114,7 +114,7 @@
     "react": "^16.3.2",
     "react-dom": "^16.3.2",
     "react-test-renderer": "^16.3.2",
-    "rollup": "^0.60.1",
+    "rollup": "^0.61.0",
     "rollup-plugin-babel": "^3.0.3",
     "rollup-plugin-commonjs": "^9.1.0",
     "rollup-plugin-node-resolve": "^3.3.0",