Revision 198098

PR:
Obtained from:
Submitted by:
Reviewed by:
1.) Rename of interface Resolveable to Resolvable.      (http://dictionary.reference.com/search?q=resolvable)
2.) Reordering of methods in AreaTreeHandler, removal of unneeded TreeExt array.
3.) Switch from AreaTreeModel.addExtension() to .handleExtension().
4.) Removal of unneeded TreeExt.getName() (unused), getMimeType() (implementation
of an Area Tree extension up to each renderer), and isResolvable() (code changed to
use instanceof operator instead).
5.) Couple of minor layout bugs fixed.