Add more constructors to ConcurrentStepException

Author: ebousse

framework/execution_framework/plugins/org.eclipse.gemoc.executionframework.engine/src/org/eclipse/gemoc/executionframework/engine/concurrency/ConcurrentStepException.java

@@ -2,8 +2,18 @@
 
 public class ConcurrentStepException extends Exception {
 
+	private static final long serialVersionUID = 9140570714416166932L;
+
 	public ConcurrentStepException(Exception e) {
 		super(e);
 	}
+	
+	public ConcurrentStepException(String message, Exception cause) {
+		super(message, cause);
+	}
+	
+	public ConcurrentStepException(String message) {
+		super(message);
+	}
 
 }