Adapt task time slicing support to unified kernel model.
As described in the Kernel Primer (v2).
Must ensure that time slicing doesn't have any effect when the current thread is cooperative OR when it has locked the scheduler. (Note: Should double check all places that make decisions based on whether a thread is cooperative to determine if it also needs to take the scheduler lock into consideration.)
Thread scheduler API(s?) are operational. Underlying code follows the revised kernel naming conventions.
Legacy scheduler APIs are operational.