* Extend RDKit::MolStandardize with a validation and standardization Pipeline
* suggested changes
* apply clang-format
* apply yapf
* MolStandardize::FeaturesValidation optionally disallow dative bonds
* add allowDativeBondType to MolStandardize::PipelineOptions
* apply clang-format
* make the API of other validation classes more consistent with MolStandardize::FeaturesValidation
* apply clang-format
* PipelineStage to enum class
remove virtual functions from Pipeline class
be explicit about enums
* light refactoring to avoid what I think is an unnecessary call to `parse`
* a bit of modernization
* make the pipeline configurable
* make parse and serialize configurable too
* switch to storing pipeline stages using uints
* add a simple test for providing a pipeline
* update pointer alignment for clang-format
* test modifying the parser and serializer
* update swig requirement
* changes in response to review
* changes in response to review
* rename PipelineResult's *MolBlock members to *MolData
* upgrade swig to 4.2 in the CI environments
* add a few missing export directives
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Co-authored-by: greg landrum <greg.landrum@gmail.com>
