New sshd syslogd ueimatch definition

This patch adds a new ueiMatch definition for sshd syslog messages.

Forgive me if I could not fully test this patch, as the correct regex for me must start by '^.*?' and not '^' (see bug http://issues.opennms.org/browse/NMS-6539).

I did test the '^.*?Authentication refused...' regular expression tough.

Cyrille Bollu