* src/server/conference.c (delete_conf): Log a message when a
conference is deleted, which includes the name of the conference
and the user ID of the person that performs the deletion.
* src/server/testsuite/config/prot-a.exp (kom_delete_conf): Expect
the above message.
* src/server/testsuite/lyskomd.0/03.exp: Ditto.
* src/server/testsuite/lyskomd.0/13.exp: Ditto.
* src/server/testsuite/lyskomd.0/32.exp: Ditto.
* src/server/testsuite/lyskomd.0/conference-cov.exp: Ditto.
* src/server/testsuite/lyskomd.0/person-cov.exp: Ditto.