[WIP] Merging the DHT and PeARS parts together

[nandajavarma]

While implementing the NAT traversal, I had to use up a lot of ports to create active UDP listeners. Since we already have active UDP listeners in our DHT, we need not over complicate things with more networking code going in. But this would mean that the DHT and the client instance can no longer remain as separate entities. We will have to fetch the URLs and peer_profile details directly from the DHT. If the PeARS instance and the DHT are parts of a single app, then variable sharing becomes easier. This is what this code does.

This is still a work in progress. The current setup does the searching with or without bootsrapping nodes. But if the bootstrapping node is behind NAT it cannot yet locate it, so will show zero results. It need heavy testing and a lot more love. This PR will be actively updated.

P. S.: To make Flask and Twisted work together, I had to do a lot of hacks here and there. We can change it in the future. Hopefully when the Django thing is ready.