Bug 123496 [IDE] Use operation validation API for IDE actions
We should use the Resources/Core operation validation API in the IDE actions for manipulating resources.
bundles/org.eclipse.ui.ide/extensions/org/eclipse/ui/actions/CopyFilesAndFoldersOperation.java
* @param source
	 *            source resource
	 * @param destination
	 *            destination resource
	 * @return boolean <code>true</code> if both resources are either linked
	 *         or unlinked. <code>false</code> otherwise.
	 */
	protected boolean homogenousResources(IResource source,
			IResource destination) {
		boolean isSourceLinked = source.isLinked();
		boolean isDestinationLinked = destination.isLinked();
		return (isSourceLinked && isDestinationLinked || isSourceLinked == false
				&& isDestinationLinked == false);
	}
	/**
	 * Returns whether the given resource is accessible. Files and folders are
	 * always considered accessible and a project is accessible if it is open.
	 * 
	 * @param resource
	 *            the resource
	 * @return <code>true</code> if the resource is accessible, and
	 *         <code>false</code> if it is not
	 */
	private boolean isAccessible(IResource resource) {
		switch (resource.getType()) {
		case IResource.FILE:
			return true;
		case IResource.FOLDER:
			return true;
		case IResource.PROJECT: