Bug 213907 Provide a copy constructor for SubqueryDefinition.
Engine need a copy constructor to generate a SubqueryDefinition from an ISubqueryDefinition and change the name of the query.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/PreparedQuery.java
{
	/**
	 * 
	 * @param baseQyeryDef
	 * @return
	 * @throws DataException