stddoclet: Add access subheadings in member summary tables

This is variation on 4148513 adding protected as keywords
to the method summary. This request suggests adding subheadings for:

   public static
   public
   protected static
   protected

Likewise, for the -private option, add subheads "private" and
package-private subheadings.

NEED TO DECIDE: For the -package option, what should the heading be
for package-private methods? Probably "package" or "package-private"

Notice this should apply to:
   Method Summary
   Field Summary
   Constructor Summary
   Inner Class Summary

NEED TO DECIDE:
When adding the subcategories, please keep [remove?] those same keywords in the
cell that contains the return type The advantage of
keeping them is that the user has the signature there, and for
long lists does not need to scroll up to find out if it's public or
protected.

Examples are at:
http://webwork.eng/products/jdk/javadoc/trial/method-summary-trials-borders.html#example9a

Example 9a is winning, but final one is not yet decided.