pgsql: Make the various places that determine the user's "home

Log Message:
-----------
Make the various places that determine the user's "home directory"
consistent. On Unix we now always consult getpwuid(); $HOME isn't used
at all. On Windows the code currently consults $USERPROFILE, or $HOME
if that's not defined, but I expect this will change as soon as the win32
hackers come to a consensus. Nothing done yet about changing the file
names used underneath $USERPROFILE.

Modified Files:
--------------
pgsql/src/include:
port.h (r1.68 -> r1.69)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/port.h.diff?r1=1.68&r2=1.69)
pgsql/src/interfaces/libpq:
fe-connect.c (r1.295 -> r1.296)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-connect.c.diff?r1=1.295&r2=1.296)
fe-secure.c (r1.62 -> r1.63)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-secure.c.diff?r1=1.62&r2=1.63)
libpq-int.h (r1.99 -> r1.100)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/libpq-int.h.diff?r1=1.99&r2=1.100)
pgsql/src/port:
path.c (r1.46 -> r1.47)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/port/path.c.diff?r1=1.46&r2=1.47)