las3_pub / predictable_parallel_patterns

Change to pure fork-join task model

See merge request !11

See the comment in the source. This race should actually not be important, but we fix it anyways for now to make the CI happy.

This should have been fine without the atomic property (as it is only a single writer and multiple readers to a single bit). Nevertheless we fixed the 'race' to remove a warning in the thread sanitizer.

This was highlighted as an issue in the steal_work routine, as frequent calls to virtual functions are expensive.

Please note that this does currently not execute, but only removed the 'old aspecs'. We are still missing launching the root fork_join task.

Add Parallel For.

See merge request !10

# Conflicts:
#	PERFORMANCE.md
#	lib/pls/CMakeLists.txt
#	lib/pls/include/pls/internal/scheduling/fork_join_task.h