Use a custom kiwix-serve index template

[rgaudin]

• Start kiwix-serve with --custom-index option
• Add a Job that creates this index.html from the Github version (pinned version) applying two patches:
  • Changing the title name (yay)
  • Adding the donorbox sticky donate button This jobs is supposed to be ran manually when we change kiwix-serve version

Fixes #295

⚠️ this is already deployed and tested. In live version, job was created targetting script in branch instead.

[rgaudin]

How should we test this (next time)? Should we deploy the same in dev.library.kiwix.org so that we can test this easily there, and assume that if it works on dev, it will work in prod?

I don't know. I tested the script and the kiwix-serve behavior locally first. Then I tested the job on the cluster (but that had no link to the prod).

Eventually I tested it in the backend to confirm it required a varnish purge (kiwix-serve) ; which it did. That was the only prod-affecting test and testing on dev would not have helped much here…