pgsql: On win32, there is currently no way to get the equivalent

Log Message:
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On win32, there is currently no way to get the equivalent function of
the "ps" argument list on Unix - meaning that there is no way to
identify for example the stats processors or the bgwriter.

This patch adds this functionality, in a bit of a crufty way. It creates
a kernel Event object with the name of what would be in the title. This
can be viewed using for example Process Explorer.

It's been very handy for me during both debugging and using. I haven't
figured a better way, but perhaps someone has one that's less crufty? If
not, here is at least a working patch :-)

Magnus Hagander

Modified Files:
--------------
    pgsql/src/backend/utils/misc:
        ps_status.c (r1.21 -> r1.22)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/ps_status.c.diff?r1=1.21&r2=1.22)