[PATCH] Verbose git-daemon logging

[PATCH] Verbose git-daemon logging

This patch makes git-daemon --verbose log some useful things on stderr -
in particular connects, disconnects and upload requests, and in such a
way to be able to trace a particular session. Some more errors are now
also logged (even when --verbose is not passed). It is still not perfect
since messages produced by the non-daemon-specific code are obviously
not formatted properly.

[jc: With minor fix up in the log line truncation, and
 use of write(2) as suggested by Linus.]

Signed-off-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <junkio@cox.net>