Remove ExecutorInvocationException

Remove: The ExecutorInvocationException. It was thrown by every function executor and function and produced unnecessary try-catchs.
RuntimeExceptions should be used as a replacement.
Performance: Skip argument validation when no parameters and no args

Add: The DefaultFunctionInvocation class tries to skip the slow argument validation process whenever there are no arguments and no parameters. That results in a better performance for functions without parameters.
Javadoc and comment improvements

Fix: Some minor javadoc and comment issues.
Update changelog