Reduce what is written by aplog_error() by excluding filename if it

is NULL, line number if it is "-", and errno if the new APLOG_NOERRNO bit
is set in level parameter.  Do it all with a lot less string copying --
use snprintf incrementally to build up the entire buffer.
When server_conf is NULL use stderr, since that is necessary to do some
things during startup and other odd cases (i.e. SEGV).
Fixed a buffer overflow with syslog stuff using sprintf().

Submitted by:	Ken Coar and Dean Gaudet
Reviewed by:	Roy Fielding


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@79331 13f79535-47bb-0310-9956-ffa450edef68