Technical communications/Dev wiki consolidation

This is related to Requests for comment/Wikitech contributors. The pages should probably be merged at some point, but for the moment I'm using this one for brain-dumping.

Issue

 * fragmentation of venues for contribution
 * fragmentation of documentation
 * awkward content living where it doesn't really belong

Proposed solution

 * 1 wiki for promoting and supporting MediaWiki software and its API to sysadmins, developers and end users.
 * 1 wiki for promoting and coordinating the open source development of MediaWiki based software projects and Wikimedia technical initiatives.

Many free software projects offer two venues like this; it's not unusual for the "official website" to be about documentation, support and promotion, and for the open development (issue tracking, feature design and RfCs, "internal" project documentation) to happen somewhere else (like SourceForge or more recently GitHub, or a  subdomain).

This distinction actually already appears in our own mailing lists:  is for MediaWiki users and support, and   discusses "technical organization of the Wikimedia projects (i.e.: MediaWiki development and Wikimedia operations).

What belongs where
To get an idea, this is how the big groups of content would be distributed:

mediawiki.org

 * MediaWiki downloading, installing, configuring, upgrading, release notes...
 * Catalog of extensions.
 * Help and Support desk.
 * Sites using MediaWiki, hosting, vendors...
 * Sysadmin hub.
 * User hub, what is a wiki, how to edit a page...
 * Developer hub, API, reference docs, howtos, tutorials...

wikitech.wikimedia.org

 * Developer access, request repository, submit a patch, code review docs...
 * Hackathons, QA weekly goals, dev trainings, tech talks, dev meetups...
 * Wikimedia Engineering and non-WMF projects, teams, status, reports, RFC...
 * Mentorship programs, Google Summer of Code, Outreach Program for Women...

Plus what is already there:
 * Labs
 * DevOps

Advantages and risks
Advantages:
 * 1 wiki for all technical contributions in the Wikimedia universe: development of MediaWiki and extensions, Wikimedia operations, Bots, Labs, etc.
 * As a corollary: More integration and collaboration between members of the tech community: developers, Operations people, bot owners and maintainers, etc.
 * Also a corollary: A single entry point for all volunteers interested in joining the community.
 * No more content on mediawiki.org that's not related to MediaWiki (mostly: Wikimedia engineering project documentation)
 * Wikitech has some nifty tools like Semantic Forms that would be super useful for volunteer involvement and project documentation and replace clunky and complicated systems currently based on LST transclusion and fragile templates.
 * Through its previous merge with Labsconsole, Wikitech is now integrated with Wikimedia Labs, and therefore Gerrit. This would greatly simplify identity and credentials management for developers.

Risks:
 * Appearance of the WMF moving to their own wiki and segregating itself from volunteer developers.
 * That won't happen if the whole community of contributors (WMF or not) agrees to make Wikitech their new home.
 * Fragmentation of MediaWiki documentation: some pages are useful to different roles e.g. 3rd party developers and code contributors.
 * We are not trying to create two segregated sites. Everything is still a click away. As long as each domain is clear we should be fine.
 * Interwiki redirects (i.e., allowing #REDIRECT foo to work automatically), common search and RSS/Atom must be explored to bridge and connect wherever makes sense.
 * There will be a temporary disruption as people change their habits.
 * Change brings disruption; it can't be avoided, but it can be planned carefully and minimized.

Steps

 * Discuss at length to plan everything, classify the content and determine what goes where.
 * Move agreed pages to Wikitech.
 * Proposal: done by guillom, Qgil and whoever else wants to help. guillom has an idea about how this could be done by a few of us. The migration itself is relatively simple and Guillom has an idea about how to do it. The complex part is to decide which pages. We could nominate pages for migration using a specific category and let everybody a chance to discuss in the category page. A big bunch of pages would be included by a common principle e.g. Category:WMF_Projects. Then we can be more conservative with the smaller pockets and individual contentious pages.
 * Clean up and organize the wikis, and cross-link where appropriate (like the main pages & sidebars).

Once the situation between mediawiki.org and Wikitech is stable:
 * Move developer content from Meta (e.g. around Wikimedia developer hub, Mobile projects, Wikidata Development) wherever is appropriate, following the same principle.
 * Invite the English Wikipedia technical community to join as well with their developer content (e.g. around w:Wikipedia:Lua, w:Wikipedia:Creating a bot, w:Wikipedia:Gadget, w:Wikipedia:Tools), especially when it's useful to other Wikimedia projects and MediaWikis. This would also apply to other generic developer documentation currently hosted in other Wikimedia projects and languages.
 * Merge usability wiki into wikitech (p-p-p-pleaaaase)