Biolink-model

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add side effect predicate
add 'abundance or activity' enum value
deprecate 'original knowledge source', add documentation to the description and examples

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minor syntax changes/typo fixes
adding requested attributes for COHD supporting data properties

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deprecated/refactored predicate hierarchy to move semantics from predicates into qualifiers (edge properties)
added several enumerations for qualifiers, depending on their usage in associations
added gene->chemical associations with restrictions on subject/predicate/object values (as defined in enumerations)
restructured annotations syntax to comply with LinkML including a change to canonical predicate and opposite syntax

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* add pydantic class to the wheel
* update LinkML dependency

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* add BioPlanet and Inxight prefixes
* rename pydantic class to model.py

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* updated documentation to reference the Biolink Model publication
* added molecular activity to pathway association
* added gene to pathway association