Allow consolidated-events ^2.0.0

None of the changes affect how consolidated-events is used in
react-waypoint.

Changelog:

- Now built with rollup ([#8](lencioni/consolidated-events#8))
- Deprecated `removeEventListener` export removed ([#13](lencioni/consolidated-events#13))
- Passive event listener test is now removed after being added ([#11](lencioni/consolidated-events#11))
- Reduced bundle size impact by replacing a class with a function ([#12](lencioni/consolidated-events#12))

package.json

@@ -67,7 +67,7 @@
     "scrollspy"
   ],
   "dependencies": {
-    "consolidated-events": "^1.1.0",
+    "consolidated-events": "^1.1.0 || ^2.0.0",
     "prop-types": "^15.0.0"
   }
 }