converted networks to new one file per network format using dev/convert_networks

If you're having trouble merging this commit, first merge this commit's parent, and then
start merging this commit and do this to apply what this commit does to your networks:

    git reset HEAD . # reset index to your copy
    git checkout HEAD . # reset tree to your copy
    rm -fr p2pool/networks p2pool/bitcoin/networks # remove added files
    dev/convert_networks # convert networks to new format (what this commit does)
    git commit # finish the merge