committablectx: simplify caching the status Previously, workingctx had custom variables for the unknown, ignored, and clean list of files of status. These then got moved to committablectx and, after the refactoring of localrepo.status, are no longer needed. We, therefore, simplify the whole mess. As a bonus, we are able to remove the need for having 'assert'.

localrepo: remove cache code now handled by _prestatus This patch removes the last of the 'working' variable that was sprinkled throughout localrepo.status which paves the way for future patches to use the object oriented design of contexts to handle calculating the status.