Add the WIP 10k ref architecture specs to HA docs
Add the WIP 10k ref architecture specs to HA docs

The 10,000 user reference architecture work is ongoing. However, we have
done some preliminary investigation and testing and have an idea of
what we think the environment might look like. In the interest of
transparency, efficiency and iteration, let's get this out there.

stoplightio/gitlabhq,stoplightio/gitlabhq,iiet/iiet-git,iiet/iiet-git,mmkassem/gitlabhq,stoplightio/gitlabhq,mmkassem/gitlabhq,iiet/iiet-git,stoplightio/gitlabhq,iiet/iiet-git,mmkassem/gitlabhq,mmkassem/gitlabhq