P2B (P2P Binary) File Format v3

P2B was created to lighten the load while transfering PeerGuardian blocklists.
It typically results in files 50% smaller than the P2P format.  Because it is a
binary format, it is _not_ recommended for general use.

P2B files specify a version number so it may be extended in the future, perhaps
to hold metadata for IPs (category, region, etc).  Please coordinate with me
(phrosty@gmail.com) if you wish to do this.

A further improvement in v2 is all range names are in UTF-8 for better
internationalization.  Parsers will NOT allow ISO-8895-1 or any other invalid
UTF-8 in range names.

Improvements in v3 are size-related: files are typically 15% smaller than P2B
v2.

There is a zlib-licensed library for C++ developers who wish to use the P2B
format available at http://peerguardian.methlabs.org

The Format (note the C-style escapes):

header     = \xFF\xFF\xFF\xFFP2B
version    = single byte, currently 0x03
namecount  = 32-bit integer in network byte order
name       = null-terminated utf-8 string
rangecount = 32-bit integer in network byte order
nameindex  = 32-bit integer in network byte order
ip         = 32-bit integer in network byte order
range      = <nameindex><start ip><end ip>

file    = <header><version><namecount><names><rangecount><ranges>