That page existed only in our redmine. Updated and added a few things,
like a paragraph about our expectations for feature contributors.
Also updated links, contacts and some other processes that may have
changed since last edition.
Added some section labels in related documents, for ease of referencing.
Task #4929
Use it to explain how to go about the sequence diagram images
(generation, updating, what is mscgen etc).
Also remove portion that referred to Sphinx builds, as these don't make
sense now.
Currently, it seems easier to upload the diagram images to git than to
try to make the image generation script work with out of the tree builds
and other corner cases.
This means, however, that one must activelly remember to update msc
diagram files, run the script and re-add new png files, if those ever
need to be updated. To raise awareness to that, a watermark was added
to the diagram images.
Also removed configuration steps that added mscgen as dependency
(locally and for workflow builds and readthedocs).
Moved devguide dir into userguide dir.
Since the devguide is now incorporated as the last chapter of the
userguide, removed build and configuration files from the devguide
dir, as these are no longer needed.
Task #4909
Juliana Fajardini