Secure a possible break out of secured code in constructor.

- Make FunctionBlockSecurityDecorator catch every throwable in
  blockConstructors, so as to avoid the Threadpool crashing on
  "throw new Error();"
Fix hang in LOGGER.

- For some reason Logger.catching(e) hangs when called with a specific
  JSON exception. Avoid this by calling e.printStacktrace instead.
Fix minor NullPointerException.

- Appeared, when calling setValue in constructor of Block.