This fixes a bug where  peer could miss pieces btpd got while the
peer was in handshake.

Also, btpd now sends multiple have messages instead of a bitfield
when it's better to do so.

Since the set hz is (almost) never achieved the denominator is now based
on the average hz the last 5 seconds.

Let the default be 8 hz for now.

Removed a try at time correction. I don't really think it'll matter and
there was a potential bug if the clock went backwards.

Removed net_by_second. Let the peer bandwidth calculation be handled in
cm_by_second.

be killed.

* Don't decrease busy count on a piece when a block arrives in end game.
  The busy count should always be zero at that stage.

Add test for program correctness.

Added test for program correctness.

totally correct. Since there's a possibility that we've assigned
requests to peer and then decreased the wanted level, we could've
missed peers with requests but a wanted level of zero.

Now we check if the peer has any requests instead.

added to the torrent list. This bug crept in because this file was
based on an earlier version of policy.c.

so it must be bug free :)

Add --with-warn option to configure, making it easy to
select between a couple of predefined warning options.

Having all warnings on and treated as errors wasn't so good,
since different versions of gcc have different warnings.
There's no need to make it harder than it should be to build
btpd.

net_generic_read use a real io_buffer and this function too.

policy on a lower level.

The net code now calls the peer code when it has read a full message.
  This has mostly involved moving code from net.c to peer.c.

* Added torrent_piece_size helper function.

*) Don't call names.
*) Don't think it's neccessary to include fixing of general bugs.

save uncomplete messages. I had forgotten about the four bytes of
message length preceding the message. A buffer overflow could occur
because of this. Ouch!

making it possible to remove peers in mid hand-
shake when removing a torrent.

instead of the ideal.

as soon as the message head was written to the network. Now it's increased
for each byte of torrent data we've written.

which may happen if some other header includes sys/queue.h.