Instagram node

This is my attempt on the Instagram node. Current example is showing the query node. Comments are welcome. I'll squash commits once we get this work into a pullable state. Thanks

The pull request is now ready @knolleary .
Rather than get both the most recent photo and most recent liked each time, each node only needs to get the most recent Thing depending on which Thing the node is configured for. That would reduce the time taken, and number of requests needed, to initalise the node.