Revert "Remove Windows syslog script and syslog.reg"

Revert "Remove Windows syslog script and syslog.reg"

This reverts commit cc44bad1f6ded6a62c9bbe4d145b5b418aa775f4, since its
assumptions were not correct.  Actually, the classic event logging is
still used by PHP, because Windows 7 is still to be supported for a
while.  Without the respective registry entries, the event log entries
show an error message regarding missing ID descriptions.

Thanks to ab@php.net for hinting at this!

Obviously, the part depending on ext/win32std has still to be
overhauled, and further improvements are conceivable; we will address
this in due course.