Changes

Lock ChangeSet: Prepare RecursiveLock to be an implementation of it's new interface

Lock ChangeSet: New RecursiveLock interface. Minor API change to of tryLock throws declaration

Lock ChangeSet (fin): Cleanup, fix and enhance RecursiveLock implementation

- RecursiveLock _is_ interface.

- Use LockFactory to create a RecursiveLock.

- Impl: RecursiveLockImpl01Unfairish
  - just using notify w/o any queue: fast
  - still enqueuing new lock-applicants if queue full (nice)
  - lock's sync extends AbstractOwnableSynchronizer and uses it (monitor)

- Impl: RecursiveLockImpl01CompleteFair
  - using queue and interrupt for correctness (slow)
  - lock's sync extends AbstractOwnableSynchronizer and uses it (monitor)

- Impl: RecursiveLockImplJava5 for using Java5's concurrency impl.
  - to verify correctness, performance and deviation of locking time

TestRecursiveLock01 new performance measurements incl. simple avrg and deviation
shows best combined performance-deviation w/ our RecursiveLockImpl01Unfairish
os Linux and MacOSX.
RecursiveLockImpl01Unfairish is the default in LockFactory.

Adding 'private' LockDebugUtil, allowing validating all holdings locks
of one thread as stack traces (Throwable).
Besides the AbstractOwnableSynchronizer utilization, this helps debugging deadlocks
and starvation very well.

RunnableTask: Allow validation whether invoking thread intends to wait for the result

minor: test/build scripts