RFE: Retire Fedora Core 4 only _after_ FC6 has been released.

[Arjan van de Ven]

> 
> "Installer alert: You do realize that this release is no longer
>   maintained actively, but has been transfered to the Fedora
>   Legacy project, which may provide community maintained
>   security updates.  If you wish to use a currently maintained
>   OS release, please upgrade to a newer Fedora Core release."

s/a currently maintained/a proactively maintained/