whereby timezone isn't an int, but tzset() exists...

This isn't a definitive fix, as there is probably an easier way of
fixing the bug...

Submitted by: Ovidiu Predescu <ovidiu@bx.logicnet.ro>

	- created a HAVE_TZSET define for this purpose

```yaml
below my signature, there are a coupls of diffs and files in a shell
archive, which were needed to build postgres95 1.02 on Siemens Nixdorfs
MIPS based SINIX systems. Except for the compiler switches "-W0" and
"-LD-Blargedynsym" these diffs should also apply for other SVR4 based
systems. The changes in "Makefile.global" and "genbki.sh" can probably
be ignored (I needed gawk, to make the script run).

There is one bugfix thou. In "src/backend/parser/sysfunc.c" the
function in this file didn't honor the EUROPEAN_DATES ifdef.
```

Submitted by:  Frank Ridderbusch <ridderbusch.pad@sni.de>

        - src/backend/access
                - no changes
        - src/backend/utils
                - mostly cosmetic changes
                - ESCAPE_PATCH Added
        - src/Makefile.global changes merged

Submitted by: Randy Kunkee <kunkee@Starbase.NeoSoft.COM>