las3_pub / predictable_parallel_patterns

The current version has race conditions and is hard to debug (especially because of the fibers, if a wrong thread executes on a fiber we get segfalts very fast). To combat this mess we now refactor the code bit by bit while also adding tests where it can be done with reasonably effort).

The project is currently really messy and there are sporadic sigsevs. This indicates that we still have a race in our code. Thread Sanitizer does not work with our current implementation, as it needs annotations for fibers.

The next step is to clean up the project and maybe add thread sanitizer support to our fiber implementation. This should help finding the remaining bugs.

The deque trades tasks when stealing. Right now only the fast local path is tested and implemented. For the next step to work we also need to add the resource stack and resource tarding to the system.

The current state shows the minimum actions taken to execute a parallel call: get the thread local, find the active frame, execute on the next frame and return to the active frame.