Add prerequisites doc

[WizardBit]

Moving "Juju Controller" and "Tunnel into the undercloud network" from the OpenStack Tutorial into their own prerequisites doc. This would make it easier to reference to in other tutorials.

I also added some formatting to the existing markdown.

[WizardBit]

@pponnuvel To render the pages correctly you'll have to pull this PR locally and build the documentation.

cd docs/
make run

http://127.0.0.1:8000/user-docs/prerequisites/
http://127.0.0.1:8000/user-docs/openstack/tutorial/

[pponnuvel]

@pponnuvel To render the pages correctly you'll have to pull this PR locally and build the documentation.

cd docs/
make run

http://127.0.0.1:8000/user-docs/prerequisites/ http://127.0.0.1:8000/user-docs/openstack/tutorial/

What I meant is that, when looking at the doc from GH itself, the link isn't working:

https://github.com/WizardBit/stsstack-bundles/blob/0c1f65674b50a63c79448ddfe8383f49a4251ff9/docs/user-docs/openstack/tutorial.md

I suspect this is because the GH renderer doesn't recognise the link without the extension.

[WizardBit]

@pponnuvel I added the static link to the file. The build action for link check failed as it does not exists yet until the PR is merged.

[pponnuvel]

LGTM - Thanks @WizardBit

[nicolasbock]

Readthedocs builds the PR, you can check it out there: https://canonical-stsstack-bundles--376.com.readthedocs.build/en/376/

[nicolasbock]

Is serverstack still up? I like the refactoring of the instructions, but we should follow up with updating where to deploy. Most of us are probably using PS7 now.

[WizardBit]

I thought serverstack was just referencing any server as this repo is public.