Syslog appender "re-add" patch

[Andreas Fester <af...@apache.org>]

Hi,

I intend to commit the attached patch. It re-adds the syslog
appender (fixes LOGCXX-66).

The memory leak which was reported some days ago should be fixed.
I dont really like the memory pools being passed from one
method to another (and probably this would not have helped here
because it would probably still have been the same pool then).
After asking on the dev@apr.apache.org mailing list and
reading http://subversion.tigris.org/hacking.html#apr-pools
and http://www.apachetutor.org/dev/pools, I think a better
solution is to use the object-specific memory pool for the
socket only (because the lifetime of the APR socket and the
lifetime of the DatagramSocket object are aligned), and use
local pools for the apr_sockaddr_info_get() call (the
apr_sockaddr_t data is not needed anymore when the method
returns).

Apart from that, the build.xml always configures the local
syslog() function to be available on UNIX and to be not
available on Windows, while the autoconf configure script
checks if the function is actually available.

Thanks & Best regards,

	Andreas