Bug 124124 [Markers] Group sorting needs criterea other than lexical value
20060117 Lexicial sorting is not good enough for the severity group as we need to sort errors before warnings and the translation of the word error may not appear lexically before warnings. The sorting of groups needs to be the same as the sort order of thier elements. This turns out to be an issue for groups contributed via attributes as well. My suggestion is that allow the group to sort either by attribute value or by name (the default) so that sort order can be supplied by the group contributor. I am including the JDT team as they may want to use this support to determine sort ordering within thier groups.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/CategorySorter.java
TableSorter innerSorter;
	IField categoryField;
	boolean reverseSort = false;
	
	private final String TAG_FIELD = "categoryField"; 
	/**
	 * Create a new instance of the receiver wrapping a sorter.
	 * 
	 * @param sorter
	 */
	CategorySorter(TableSorter sorter) {
		innerSorter = sorter;
	}
	/**
	 * Compare obj1 and obj starting with field depth.
	 * 
	 * @param obj1
	 * @param obj2
	 * @param depth
	 * @param continueSearching
	 * @return int
	 * @see ViewerSorter#compare(Viewer, Object, Object)
	 */
	int compare(Object obj1, Object obj2, int depth, boolean continueSearching) {
		if (obj1 == null || obj2 == null || !(obj1 instanceof MarkerNode)
				|| !(obj2 instanceof MarkerNode)) {
			return 0;