Amélioré Documentation

Added the Websites specification

Internal: docs/specs/WEBSITES.md specifies websites made of uploaded files, one Websites area for both kinds of website, and one domain status across DNS, Mail and Websites.

Internal: added docs/specs/WEBSITES.md, the version 1 specification for websites made of a person's own files (uploading files, folders and ZIPs in the browser, versions with restore, serving on each website's own origin, files built from a Git repository), for renaming Website Builder to Websites with two kinds of website, for turning an editor website into files, and for one domain status shared by the DNS page, the Mail domain page and the Custom domain page, with a www companion host. Eleven decisions for the owner are listed with recommendations. Nothing is built yet.