Expanded the heteronuclear T1 v3.1 module to include all tag names.
The version string is now being printed, rather than recreating it.
The sub-revision number is now also extracted and stored.
Added the v2.1 _Molecular_mass tag.
Changed the molecular weight variable name.
The entity saveframe has been significantly expanded and v2.1 is now supported.
The revision number is no longer set to 0 if it doesn't exist.
Better print out of the NMR-STAR version number.
Missing import.
The NMR-STAR version singleton now does all of the version number processing.
