Add an operation using a semaphore to test 004-ThreadStress.

Add a new QueuedWait operation requiring the acquisition of
a permit from a java.util.concurrent.Semaphore, to exercise
java.util.concurrent.locks.AbstractQueuedSynchronizer (used
in the implementation of java.util.concurrent.Semaphore) in
004-ThreadStress.

Also add missing command-line options and documentation for
existing operations.

Test: art/test/testrunner/testrunner.py -t 004-ThreadStress
Bug: 63822989
Change-Id: I99e55969a0df6565a4900ea3c14bf55a616c46a3