p2p/discover: persistent node database

godeps: refresh leveldb, clean up stale dependencies

Conflicts:
	rpc/api.go

Whisper cleanup, part 3

Ref: https://github.com/Gustav-Simonsson/go-ethereum/commit/21c4c155ee68890a069654dcc5bc083a867f65cd

Remove old logger from RPC pkg

Add privkey loading to block tests

And output as quantity, not data

General fixes