createLanguageSpecificDSAHelper fails when doing a clean all #24
Description
in the builder (https://github.com/eclipse/gemoc-studio-execution-moccml/blob/master/ccsljava_xdsml/plugins/org.eclipse.gemoc.execution.concurrent.ccsljavaxdsml.ui/src/main/java/org/eclipse/gemoc/execution/concurrent/ccsljavaxdsml/ui/builder/GemocLanguageDesignerBuilder.java), the createLanguageSpecificDSAHelper fails with no class def found when doing a clean all on the workspace
this is because the classpath lookup tries to search classes that are not built yet.
This generator should ensure that no builder is currently running on dependency projects before generating these helper classes