Implement Java validation rules

Currently a project validates in some cases, even if it should not do so.

Implement these checks (via XSD 1.1 if possible):

https://gitlab.com/al.schwinn/silecs-eclipse-plugin/-/blob/RestructureSilecsDeploy/silecs-eclipse-plugin/src/java/silecs/control/validation/internalRules.java

FOSS Java validation does not support xds 1.1, though probably xmllint does so .. to be checked.