First approach at a proper overview in the docs

[jsma]

NOTE This is not ready to merge yet but want to get feedback on this work-in-progress.

Added a stub for editing basics doc that is focused on non-technical audiences.
Added to the 'how to contribute' to explain how to set up local environment for testing documentation changes.

[evildmp]

We use (or should) British English for django CMS docs.

[evildmp]

Can we have a chat about this on the #django-cms IRC channel (freenode.net)? It'll be easier to do it there, for the high-level view.

[coveralls]

Coverage decreased (-0.1%) to 90.704% when pulling 2b24ed2 on jsma:documentation into 2fa7c67 on divio:develop.

[digi604]

lgtm

[evildmp]

Hi John. #3557 incorporates your changes, in a new structure (with the user-oriented material in the section user).

[jsma]

Thanks! I'll take a look and give feedback when I get a chance, has been a very busy past few days but I do have loads of screenshots ready to go for the end-user documentation. Should I work off your branch then or will these changes be merged soon?

[evildmp]

I think it would make sense if we both worked off this branch for now, and made sure we kept each other up-to-date with progress. But, I would like to get this merged sooner rather than later.