Require protocol version 80601.
Require protocol version 80601.

Bump protocol version for the 2000 -> 1000 headers change and only
connect to peers using the new version for I0coin Core.

domob1812/i0coin,domob1812/i0coin,domob1812/i0coin,domob1812/i0coin,domob1812/i0coin,domob1812/i0coin