Proposal : Get rid of this git integration

[gene1wood]

I propose that we

• get rid of this repo
• take any wiki pages that we feel are un-wiki enough to warrant wanting to carefully track their history via git, and move them to https://github.com/mozilla/infosec.mozilla.org/
• replace any pages that are like that on wiki.mozilla.org with a redirect to the infosec.mozilla.org page
• have all remaining pages just be updated dynamically in media wiki like a normal wiki

[SpikeUK]

I agree with this proposal.