[Azoth] Support commands with multiple names.
[Azoth MuC] Added /topic synonym for #1664.
[Azoth Xoox] No use in const ref to int.
[Azoth Xoox] Return proper entity time in GetClientInfo().

Use entity's time zone.
[Azoth Xoox] Return client_tzo as well in GetClientInfo().
[Azoth MuC] Proper /time display, closes #1657 again.