added constraint detection

...ster/masterthesis/Testgenerator/migration/ActionType.java

...asterthesis/Testgenerator/migration/MigrationService.java

...s/Testgenerator/rest/service/change/ChangeController.java

...erthesis/Testgenerator/rest/service/test/TestService.java

.../fhmuenster/masterthesis/Testgenerator/yaml/Activity.java

...ter/masterthesis/Testgenerator/yaml/ChangeConstraint.java

.../de/fhmuenster/masterthesis/Testgenerator/yaml/Event.java

...enster/masterthesis/Testgenerator/yaml/MigrationYaml.java

Testgenerator/src/main/resources/migration.yaml

...generator-web/src/app/components/test/test.component.html

...stgenerator-web/src/app/components/test/test.component.ts

...or-web/testgenerator-web/src/app/models/variable-value.ts