[Jenkins-infra] LTS RC push

[Oliver Gondža]

Mainly to kohsuke,

I am trying to do the full dance to have the bits pushed but run into a 
problem or two. After I have `make war.publish`ed, the rc does not seem 
to get to the mirrors at all (even after I have fixed the symlink [1]) 
and the text with the latest version does not work since we moved away 
from PHP[2].

Is there anything I skipped? I am willing to spend some more time on 
this but at this point I can use some guidance.

In the end, I would like the TLS RC web page to be smart enough not to 
offer the RC once its released variant is available (during backporting).

[1] https://github.com/jenkinsci/packaging/pull/45
[2] https://github.com/jenkins-infra/jenkins.io/pull/79

-- 
oliver