updated static_seed_nodes.txt, added pnSeed.txt containing seeds from pnSeed[] (https://github.com/bitcoin/bitcoin/commit/74fbb151de21ca8d94dc39482fd4a95bc3b7e529#src/net.cpp) 30% of the 600 nodes responsed to version msg from bitnodes, extended seeds with nodes from http://blockchain.info/connected-nodes, record depth in jobs table and exclude seed node from nodes table only if it does not respond to version message