Attribute display setting -> can't use NOT rule

[Ainschy]

Checklist before I submit this issue report

I confirm that:

• [X] I have tested this with the latest version available
• [X] I have read documentation @ http://metamodels.readthedocs.org/en/ or http://metamodels.readthedocs.org/de/
• [X] I have checked the Contao community forums for references https://community.contao.org/
• [X] I have checked existing issues for duplicates and found none @ https://github.com/MetaModels/core/issues?q=is%3Aissue

My environment is:

(Please fill in the actual values from your environment - check Contao Manager or use composer show)

Key	Value	Comments
PHP version:	7.2
Contao version:	4.4.46
MetaModels version:	2.1.7
Installed MetaModels packages:	bundle-all
DCG version:	2.1,5

Issue description

To invert an rule i cant set it into a NOT Rule, like OR or AND. This option is missing.

Steps to reproduce

1. add a rule for display a attribute
2. add rule NOT
3. try to move display rule into NOT rule like AND or OR Rule

Describe the behaviour of the application

i dont't like to display a attribute when an other attribute (select) is blank.

Screenshot

[zonky2]

Change to https://github.com/contao-community-alliance/dc-general/issues/515

[zonky2]

fix https://github.com/MetaModels/core/pull/1368

[zonky2]

fixed