[Triumf-linux-managers] update to triumf-sl-yumconf SL 5.2 only

[Kelvin Raywood]

If you have installed SL 5.2 from the TRIUMF kickstart, then you will 
get an automatic update to "triumf-sl-yumconf" .  This is the rpm that 
provides the yum [1] configuration appropriate for a TRIUMF workstation.

The update adds the CentOS-5 signing key to the list of keys used by SL. 
  This is needed because SL redistribute some of the CentOS rpms.

Kel Raywood
TRIUMF Network and Computing Services