- BUGFIX getValueFromOtherStep() calls protected MultiForm::$session
- Use the provided `MultiForm::getMultiFormSession()` method to get the proper result.
- BUGFIX getValueFromOtherStep() only fetches subclass steps for the session disallowing access to other class step data
* removed @package references
* included stubs in the test namespaces
* updated various return types
* updated composr psr4 autoload classes
* doc update