We don't actively moderate these comments, and they range from
out of date, to inflammatory, to spam. Going forward, improvements
to the docs should be done via a PR, and questions should go on
StackOverflow where they can be curated and kept up to date by
AngularJS developers who help out there.

Closes #4904

Closes #4811

The grouping of the different versions was not correct for the new 1.2.0+ releases.
Now versions are marked as stable only if they have an even number it the minor version
position (e.g. 1.0.8, 1.2.1, 1.2.0-abcde) and they are not an RC version, (e.g. 1.0.0rc3,
1.2.0-rc2).

Closes #4908

Before, there we multiple overview docs:
- guide/overview
- guide/introduction
- guide/dev_guide.mvc
- guide/dev_guide.mvc.understanding_model
- guide/dev_guide.mvc.understanding_view
- guide/concepts

Now we have:
- guide/introduction: High level description of Angular with the key benefits but without code or any concrete concepts
- guide/concepts: explains all important concepts with a simple example and contains deep links to the other parts of the guide.

 All the old information was moved into existing documents or deleted when they were duplicates.

When navigating to URLs such as
docs.angularjs.org/api/ng#filter, the browser
was not able to navigate to the named anchor,
"filter," because the anchor did not yet exist
in the DOM.

This fix uses the $anchorScroll service
to automatically scroll to the right place when
the content has been added to the page.

Fixes #4703

Fixes some warnings during docs generation.

Closes #4673