made constraints a littel less strict

...s.descartes.dml.mm.applicationlevel/model/functions.ecore

...rtes/dml/mm/applicationlevel/functions/DoubleLiteral.java

...artes/dml/mm/applicationlevel/functions/DoubleSample.java

...m/applicationlevel/functions/ExponentialDistribution.java

...scartes/dml/mm/applicationlevel/functions/IntLiteral.java

...escartes/dml/mm/applicationlevel/functions/IntSample.java

...dml/mm/applicationlevel/functions/NormalDistribution.java

...applicationlevel/functions/impl/FunctionsPackageImpl.java

...m/applicationlevel/functions/util/FunctionsValidator.java

...l/parameterdependencies/ParameterdependenciesFactory.java

...erdependencies/impl/ParameterdependenciesFactoryImpl.java

...ider/ParameterdependenciesItemProviderAdapterFactory.java

...eterdependencies/util/ParameterdependenciesValidator.java

...applicationlevel/repository/util/RepositoryValidator.java

.../dml/mm/applicationlevel/system/util/SystemValidator.java