Internal:Supporting multiple conferences

The Queering Wikipedia 2023 Conference is interested in using wikiconference.org to host their site, and we seem to be in consensus to support that.

List of proposed changes to be made to the site:
 * Update serverside variables (site name, etc.) from "WikiConference North America" to "WikiConferences" or something similar.
 * Update the site logo to a generic to-be-made WikiConference logo that isn't North America specific.
 * Move all WCNA pages to under /WCNA (e.g.  ->  ).
 * Maintain redirects so existing links don't break.
 * Likewise, move all  pages to.
 * Queering Wikipedia's prefix will be QW. (Or perhaps QW23 to accommodate multiple years?)
 * Expand sidebar to support multiple conferences. The relevant links could be in groups with the top group oriented to the next upcoming conference, and others prepared below