convert "from_organism" predicate to MemberLink format to display sars2 genes/proteins as a pathway

[mjsduncan]

in coronavirus_biogrid.py, change senamatics of association of SARS-CoV-2 genes and proteins from current format to pathway semantics so the set of SARS2 genes can be displayed like a pathway in the gene-annotation service.

(EvaluationLink
     (PredicateNode "from_organism")
     (ListLink
          (GeneNode "M")
          (ConceptNode "ncbi:2697049")))

should be

(MemberLink
     (GeneNode "M")
     (ConceptNode "ncbi:2697049"))