Revision 1245

Add XML validation to some of the tests. Validation will only be
done if pyRXP is installed (http://reportlab.com/xml/pyrxp.html).
To make the DTD available to the test cases it's moved into
Resources/XML

* Resources/XML/thuban.dtd: New. This is now the real Thuban DTD
for versions up to and including 0.2. Two slight changes: added an
encoding specification and fixed the comment which refered to
GRASS, not Thuban

* test/xmlsupport.py: New support module for tests involving XML.
Currently there's a mix-in class for XML validation.

* test/test_xmlsupport.py: New. Tests for the xmlsupport module

* test/test_save.py (SaveSessionTest): Derive from ValidationTest
so that we can validate the
(SaveSessionTest.testEmptySession)
(SaveSessionTest.testSingleLayer)
(SaveSessionTest.testSingleLayer)
(SaveSessionTest.testLayerProjection)
(SaveSessionTest.testRasterLayer)
(SaveSessionTest.testClassifiedLayer): Validate the generated XML

* test/runtests.py (main): Call print_additional_summary instead
of print_garbage_information

* test/support.py (resource_dir): New function to return the
"Resource" subdirectory
(print_additional_summary): New function to combine several
summary functions
(run_tests): Use print_additional_summary instead of calling
print_garbage_information directly