Bug 331259 [Compatibility] 3.x commands no longer have states available to them
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/Parameter.java
* Whether the parameter is optional (as opposed to required).
	 */
	private final boolean optional;
	/**
	 * The type for this parameter. This value may be <code>null</code> if the parameter is not
	 * typed.
	 */
	private final ParameterType parameterType;
	/**
	 * The string representation of this object. This string is for debugging purposes only, and is
	 * not meant to be displayed to the user. This value is computed lazily, and is cleared if one
	 * of its dependent values changes.
	 */
	protected transient String string = null;
	/**
	 * The actual <code>IParameterValues</code> implementation. This is lazily loaded from the
	 * <code>valuesConfigurationElement</code>, to avoid unnecessary class-loading.
	 */
	private transient IParameterValues values = null;
	/**
	 * Constructs a new instance of <code>Parameter</code> with all of its values pre-defined.
	 * 
	 * @param id
	 *            The identifier for this parameter; must not be <code>null</code>.
	 * @param name
	 *            The name for this parameter; must not be <code>null</code>.
	 * @param values
	 *            The values for this parameter; must not be <code>null</code>.
	 * @param parameterType
	 *            the type for this parameter; may be <code>null</code> if the parmeter doesn't