* Add inventory:setList(list) and inventory:getList() to inventory element.
This allows multiple inventory elements with the same list name but different inventory locations.
Example: the "main" list in a chest and the player's "main" list.
- self.data.items is initialized once in onCreate
- There is no label implemented
- addItem returns index for later direct access to the item by getItem()
* Views and Containers support
* completed the checkbox-fix
* Add getContainerState() to the documentation
* changed implementation for fields processing
Removed again _sfs_process_value_ and _sfs_process_action_
use element:submit() and element:setValue() instead utilizating new state:_get_element_recursive_()
Additional bugfix: container location was missed
* runtime optimization. Do _get_element_recursive_ once for setValue and submit
