Additional fix to catchup header requesting, Electrum manually fetched the last 50 headers if there were 50 or less to get, rather than asking for a chunk.  Now that we can request precise ranges of headers, we may as well always just request the maximum and it'll be capped by the server's current tip.
Additional fix to catchup header requesting, Electrum manually fetched the last 50 headers if there were 50 or less to get, rather than asking for a chunk.  Now that we can request precise ranges of headers, we may as well always just request the maximum and it'll be capped by the server's current tip.

fyookball/electrum,fyookball/electrum,fyookball/electrum