RE: libpq debug log

Hi,

I update patch to improve PQtrace(); output log message in one line.
Please find my attached patch.

How it changed:
> > The basic idea being:
> >
> > - Each line is a whole message.
> > - The line begins with <<< for a message received and >>> for a message
> sent.
> > - Strings in single quotes are those sent/received as a fixed number of
> bytes.
> > - Strings in double quotes are those sent/received as a string.
> > - 4-byte integers are printed unadorned.
> > - 2-byte integers are prefixed by #.
> > - I guess 1-byte integers would need some other prefix, maybe @ or ##.

New log output examples:
The message sent from frontend is like this;
2019-04-04 02:39:51.488 UTC  > Query 59 "SELECT pg_catalog.set_config('search_path', '', false)" 

The message sent from backend is like this;
2019-04-04 02:39:51.489 UTC  < RowDescription 35 #1 "set_config" 0 #0 25 #65535 -1 #0


Regards,
Aya Iwata