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Task started out as a self-organizing parallel-make algorithm, but ended up becoming a half-broken wait-die algorithm. When a contended object is already locked, Tasks enter a FIFO queue to restart and acquire the lock. This is the "die" part of wait-die (all locks on an Exclusion are non-blocking, so no Task ever does "wait"). The lock queue is FIFO wrt _lock acquisition order_, not _Task age_ as required by the wait-die algorithm. Make it a 25%-broken wait-die algorithm by sorting the Tasks on lock queues in order of Task ID, i.e. oldest-first, or FIFO wrt Task age. This ensures the oldest Task waiting for an object is the one to get it when it becomes available, as expected from the wait-die algorithm. This should reduce the amount of time Tasks spend on the execution queue, and reduce memory usage by avoiding the accumulation of Tasks that cannot make forward progress. Note that turning `TaskQueue` into an ordered container would have undesirable side-effects: * `std::list` has some useful properties wrt stability of object location and cost of splicing. Other containers may not have these, and `std::list` does have a `sort` method. * Some Task objects are created at the beginning and reused continually, but we really do want those Tasks to be executed in FIFO order wrt submission, not Task ID. We can exclude these tasks by only doing the sorting when a Task is queued for an Exclusin object. Signed-off-by: Zygo Blaxell <bees@furryterror.org>