Linking to internal sections is broken

According to https://mkdocs.readthedocs.io/en/0.9/user-guide/writing-your-docs/ the syntax for linking to sections in internal pages is supposed to be something like:

[project license](about.md#license) for further details.

However, links like these do not work on readthedocs.io. E.g, on this page

http://grr-doc.readthedocs.io/en/v3.2.2/deploying-grr-clients/overview.html

the html anchor tag 'Linux instructions' has the href attribute

http://grr-doc.readthedocs.io/en/v3.2.2/deploying-grr-clients/on-linux.md#uninstalling-grr

which goes to a page that doesn't exist on the documentation site ("SORRY This page does not exist yet.").

Note that the '.md' in the hyperlink url does not get replaced with '.html'.

Here are all the places where we try to link to sections in internal pages:

```text
$ grep * -R -e 'md#'
deploying-grr-clients/overview.md:A quick manual on how to remove the GRR client completely from a machine is included in the platform-specific docs: [Windows instructions](on-windows.md#uninstalling-grr), [OSX instructions](on-mac-os-x.md#uninstalling-grr), [Linux instructions](on-linux.md#uninstalling-grr)
faq.md:time](admin.md#building-clients-with-custom-labels-multi-organization-deployments),
faq.md:system](user_manual.md#artifacts).
faq.md:AdminUI](admin.md#authentication-to-the-admin-ui)
maintaining-and-tuning/scaling.md:The [GRR server components](implementation.md#grr-component-overview)
release-notes.md:versions](admin.md#client-and-server-version-compatibility-and-numbering).
release-notes.md: [here](faq.md#what-operating-system-versions-does-the-client-support)
release-notes.md:versions](admin.md#client-and-server-version-compatibility-and-numbering).
```