Bug 317954 Version deltas file so that incompatible changes will be ignored
The deltas file needs to be versioned so that incompatible changes will be discarded allowing the workbench to be constructed as if there were no deltas in existence.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/XMLModelReconciler.java
return featureName.equals(ELEMENTCONTAINER_SELECTEDELEMENT_ATTNAME) ||
		
				featureName.equals(HANDLER_COMMAND_ATTNAME) ||
				
				featureName.equals(KEYBINDING_COMMAND_ATTNAME) ||
				
				featureName.equals(PLACEHOLDER_REF_NAME);
	}
	/**
	 * Returns whether the feature is a reference to another object.
	 * 
	 * @param featureName
	 *            the name of the feature
	 * @return <code>true</code> if this particular feature is a reference to another object,
	 *         <code>false</code> otherwise
	 */
	private static boolean isSingleReference(String featureName) {
		return isDirectReference(featureName) || isIndirectReference(featureName);
	}
	/**
	 * Returns whether the feature is a list of object references.
	 * 
	 * @param featureName
	 *            the name of the feature
	 * @return <code>true</code> if this particular feature is referring to a list of object
	 *         references, <code>false</code> otherwise
	 */
	private static boolean isChainedReference(String featureName) {