Archive Reorganisation: Components

Following the upload permission changes described in archive-reorganisation-permissions, the distinction between the main and universe components is in many ways no longer as helpful as it used to be. It no longer corresponds to upload privileges in any firm way, and it does not form a superset of the packages installed by default for all Ubuntu flavours. main was originally intended to be a concise way to express what parts of Ubuntu were supported by Canonical. This model was conceived in a much simpler world - in fact, it predates the existence of an Ubuntu development community! - and it is showing its age.