relax SVN archive

Changed the path to the PDB file to not be absolute.

Wrote the structural object base class method from_xml().

Updated the structure results file.

Renamed an incorrectly named variable.

Added the code to from_xml() to load the structural data.

The from_xml() structural object method needs to be implemented.

Shifted the structural data to the end of the XML results file.

This is in preparation for dumping all the structural info into the file.

The basic structural object data is now converted to XML in the results file.

Shifted the pipe container xml_create_str_element() method to the to_xml() structural object method.

Added some checks to the test_load_results() system test.

Added a system test to check the loading of a PDB file using the information in a results file.