Created the Structure.test_bug_23293_missing_hetatm system test.
This is to catch bug #23293 (https://gna.org/bugs/?23293), the PDB HETATM loading error whereby the last HETATM record is sometimes not read from the PDB file.
Authored by: bugman 2015-02-19
Parent: [r27666]
Child: [r27668]