More logging statements and tests, tests pass apart from IllegalMonitorStateException
Catch IllegalMonitorStateException in generator shutdown

I'm not sure why this happens, but ignoring it should be harmless.

Exception in thread "random" java.lang.IllegalMonitorStateException
        at java.util.concurrent.locks.ReentrantLock$Sync.tryRelease(ReentrantLock.java:155)
        at java.util.concurrent.locks.AbstractQueuedSynchronizer.release(AbstractQueuedSynchronizer.java:1260)
        at java.util.concurrent.locks.ReentrantLock.unlock(ReentrantLock.java:460)
        at java.util.concurrent.ArrayBlockingQueue.put(ArrayBlockingQueue.java:327)
        at org.textensor.stochdiff.numeric.math.MultipathRandomGenerator$Filler._run(MultipathRandomGenerator.java:129)
        at org.textensor.stochdiff.numeric.math.CachingRandomGenerator$Filler.run(CachingRandomGenerator.java:33)
        at java.lang.Thread.run(Thread.java:722)
Exception in thread "random" java.lang.IllegalMonitorStateException
        at java.util.concurrent.locks.ReentrantLock$Sync.tryRelease(ReentrantLock.java:155)
        at java.util.concurrent.locks.AbstractQueuedSynchronizer.release(AbstractQueuedSynchronizer.java:1260)
        at java.util.concurrent.locks.ReentrantLock.unlock(ReentrantLock.java:460)
        at java.util.concurrent.ArrayBlockingQueue.put(ArrayBlockingQueue.java:327)
        at org.textensor.stochdiff.numeric.math.SimpleCachingRandomGenerator$Filler._run(SimpleCachingRandomGenerator.java:31)
        at org.textensor.stochdiff.numeric.math.CachingRandomGenerator$Filler.run(CachingRandomGenerator.java:33)
        at java.lang.Thread.run(Thread.java:722)
Remove some debugging statements to speed things up
Downgrade to Java 6, jrat doesn't support Java 7
Keep generated number in normal arrays

This should give a tiny speedup.
Make queue settings configurable
Catch IllegalMonitorStateException in generator shutdown

The same logic as in SimpleCachingRandomGenerator applied
to MultipathRandomGenerator.