Rework workflow documentation

The workflow documentation is a bit of a mess. Rework the documentation:

• Split the details out of the platform guide, making it a better high level overview of Apertis targeted more at selling the platform.
• Create an architectural document covering the basics of the Apertis workflow and how the tools used by Apertis fit together. Use pictures to help explain.
• Detailed information about workflows shifted to guides
  • Packaging guide starting to be restructured to better cover workflows by adding sections.
  • Separating out description of component repository layout into its own guide.
  • Shift image creation details to Image building guide.

While I've noticed:

• Packages have been moved from repository based sub-directories under pkg/ to pkg/ its self. Update the URLs used on the website to reflect this.

Signed-off-by: Martyn Welch martyn.welch@collabora.com

content/architecture/workflow-guide.md

@@ -69,15 +69,15 @@ configured architectures (`x86_64`, `armv7l`, `aarch64`) and publishing the
 resulting binary packages in signed APT repositories. Each package is built in
 a closed, well-defined environment where OBS automatically installs all the
 build tools and resolves dependencies from a clean state using the packages it
-has built already: if any dependency is missing the build fails. Any build
+has built already: if any dependency is missing, the build fails. Any build
 failures are reported back to the relevant GitLab pipeline and to the
-appropriate developer(s).
+appropriate developers.
 
 ![Binary package generation from source change](/images/workflow_binary-package-generation.svg)
 
 {{% notice info %}}
-Whilst the automated workflows described here provide a robust solution for
-ensuring package quality and modularity these workflows clearly do not meet the
+While the automated workflows described here provide a robust solution for
+ensuring package quality and modularity, these workflows clearly do not meet the
 needs of a developer actively developing or debugging a code base. To meet this
 need, Apertis provides tools to ease
 [development and testing of applications on top of Apertis]({{< ref "ade.md" >}})