index.html: Update some links
index.html: Update some links

Need to use https://! Also, mjanja.co.ke moved to mjanja.ch a few
months ago.

Signed-off-by: Alan Orth <c25dd0841d5fa94899de8e3e4e0aaeefb868a1ba@gmail.com>

ilri/hpc.ilri.cgiar.org-mirror,oguya/mirror.mjanja.co.ke