* Fixes#9068
* fix a problem with empty labels in s-group parsing
* fix empty column names in smiles suppliers
* add the check to setPODVal()
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Co-authored-by: = <=>
* initial addition of MT support to MolStandardize
* do the other inplace functions
* add mt ops to python wrappers
including tests
* release the GIL
* remove exploratory code added during dev
* make normalizer thread safe
* refactor some repeated code
* some initial work...
Still some real questions here about what should be done with dp_mol data members
* add some tests for move semantics of Dict and Props
remove extraneous clear()
* more in-depth testing of the molecule results
* test refactoring
* improve the molecule move test
* fix some leaks found by valgrind
the new tests are now all clean in valgrind
* additional classes
QueryAtom, QueryBond, RingInfo, Conformer
* get swig working again.
Not sure why this is necessary, but SWIG is a mysterious beast
* fixes in response to review
* updates in response to review