- The condition variable implementation "lost" a signal to
WaitOnSingleObject when a semaphore was released.
- The signal could be consumed by a new call to pthread_cond_wait
before all waiting threads had awoken.
- The new implementation of pthread_cond_* uses events
instead of semaphores. It also uses an extra lock to protect entry
into new cond wait before the broadcast has finished.
- Use same precision (milliseconds) for all time functions
used when calculating time for pthread_cond_timedwait
- Use 'GetSystemTimeAsFileTime' for both start and curr time
