Changes

Bug 1213 - RecursiveThreadGroupLockImpl01Unfairish.unlock() always
interrupts original-owner, even if not waiting at unlock()
RecursiveThreadGroupLockImpl01Unfairish.unlock():
An interrupt() is always issued from group members on the original
owner.
This shall only happen, if the original owner is waiting within unlock()
for all group members to be unlocked.
This extra interrupt causes side-effects, see Bug 1211.
Only issue the interrupt to wake-up the original owner iff waiting
within unlock!
+++
RecursiveLockImpl01CompleteFair:
 Issue 'Thread.interrupted()' to clear a slipped interrupt
 call after while-loop.

SingletonJunitCase: Allow explicit disabling singletonLock to allow
manual test cases to run concurrently

Bug 1213: Expose InterruptSource, SourcedInterruptedException and
InterruptedRuntimeException
- InterruptSource interface declares methods to retrieve
 the source of a Thread.interrupt() call.
- InterruptSource.Thread implements InterruptSource,
 i.e. allows code running within such thread to learn about
 the interrupt source (stack trace).
- SourcedInterruptedException is a InterruptedException specialization
 which may include the source of the causing Thread.interrupt() call.
- InterruptedRuntimeException
 An unchecked RuntimeException propagating an InterruptedException
 where handling of the latter is not desired.
 The causing InterruptedException may be of type
SourcedInterruptedException,
 hence a detailed stack trace analysis might be possible.

Bug 1213 (related): Fix TaskBase, RunnableTask and FunctionTask
implementation and semantics
- TaskBase
 - requires 'volatile boolean isExecuted' for atomic query of same
semantics
 - fix isInQueue(): condition was reverse in regars to 'isExecuted'
 - expose 'Thread getExecutionThread()' as learned within run() method.
- RunnableTask
 - deprecate: 'static invoke(final boolean waitUntilDone, final Runnable
runnable)',
   since it's nonsense, use runnable.run() instead.
  - 'static RunnableTask invokeOnNewThread(..)'
   - uses InterruptSource.Thread
   - Persistent-Wait
   - Cancelable using InterruptedRuntimeException
- FunctionTask
 - deprecate 'static <U,V> U invoke(final boolean waitUntilDone, final
Function<U,V> func, final V... args)',
   since it's nonsense, use func.eval(args) instead.
  - 'static FunctionTask<U,V> invokeOnNewThread(..)'
   - uses InterruptSource.Thread
   - Persistent-Wait
   - Cancelable using InterruptedRuntimeException

Bug 1213: Refine changes .. comments and API
- Use InterruptSource.Thread.create(..),
 while reducing InterruptSource.Thread ctors to 3 variants.
- Use InterruptSource.Thread instead of java.lang.Thread where possible
- Use SourcedInterruptedException where possible
- SingletonInstanceServerSocket: start(), stop() and run()
 - Persistent-Wait and Cancelable
- Add @since 2.3.2

Bug 1213: Use InterruptSource.Thread