onUrisReady has been moved from VIE.js to extender.js

As a result of a hack onUrisReady was still present in vie.js without being pushed to the VIE repo. Since onUrisReady is an extension by BnP to VIE, it has now been moved to extender.js.
Merge pull request #2 from learning-layers/onUrisReadyMoved

onUrisReady has been moved from VIE.js to extender.js