fix two bugs: first, only restore the team leader of the current TLS worker state has a worker depth greater than 0. restoring when a worker depth is 0 will violate cilk assertions because there will never be a If the worker depth is 0 then the next full frame will be executed anyways on the next scheduler loop in pop_next_frame(). Second, fix an initialization bug in worker promotion to a concurrent worker where the fibers array could be read from before the call to memset to null out the array which caused segfaults if an eager reader snuck in and tried to steal a garbage value from the array.
Merge branch 'concurrent_cilk' of github.com:iu-parfunc/concurrent_cilk into concurrent_cilk