review cray-support page

[boegel]

https://docs.easybuild.io/cray-support

Maybe we need to ask @lucamar or @victorusu for some input on this?

We should definitely:

• remove e-mail addresses
• add some historical info
• add a pointer to https://github.com/eth-cscs/production

[lucamar]

Thanks @boegel, I agree with your suggestions:

• I would also remove the versions of the software mentioned since they are obsolete and add more items to the list
• The pointer might be a link to the easybuilders mirror of the CSCS production repository
• It might make sense to integrate part of the Cray tutorial in the Cray support page of the documentation