Bug 203838 [Markers] [Markers] clicking on column headers does not sort table
I20070918 Clicking on any of the column headers does not sort based on the relevant column.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/provisional/views/markers/api/MarkerField.java
* 
	 * @return int
	 */
	public int getDefaultDirection() {
		return ASCENDING;
	}
	/**
	 * Return the id for the receiver.
	 * 
	 * @return String
	 */
	public String getID() {
		return configurationElement.getAttribute(MarkerSupportConstants.ATTRIBUTE_ID);
	}
	/**
	 * Return the image for the receiver. By default return <code>null</code>.
	 * 
	 * @param item
	 * @return The image value of the object for this particular field to be
	 *         displayed to the user or <code>null<code>.
	 */
	public Image getImage(MarkerItem item) {
		return null;
	}
	/**
	 * Return the value for a marker.
	 * 
	 * @param marker
	 * @return String
	 */