potentially parse version packet.
use just "block"
implement "addr" packet.
add "inv" packet.
add "getdata" packet.
add "getblocks" packet handling.
implement "getheaders" packet handling.
add "tx" packet handler.
add "block" packet handler.
comments.
add "getaddr", "mempool", and "ping" handlers.
"pong" handler.
add "alert" handler.
add "filterload" handler.
add "filteradd" packet.
all packets finally implemented.
get handlers compiling.
"gedata" compiling.
"getblocks" compiling.
"getheaders" compiling.