Make ChannelInputStream respect connection timeout

[jpstotz]

If the ChannelInputStream does not get new data it waits without timeout.

This patch makes ChannelInputStream respect the timeout configured in the Connection.

fixes #731

[jpstotz]

In my first version I used Object.wait(long) but this method has the drawback that you can not identify if it returns because of a notifyAll() call or if a timeout occurred.

Therefore I changed the implementation from synchronized(buf) {..} blocks and Object.wait(..) Object.notifyAll() calls to ReentrantLock and Condition as the latter allows us to detect if there was a timeout or not when using
Condition.await​(long time, TimeUnit unit)