Migrating info from gcmdr to nexsons

using peyotl d69c8b180fce7703c7203a0b51712eab57e2988c
dev/decorate_pg_studies_with_gcmdr_info.py
to set:
  ^ot:candidateTreeForSynthesis
  ^ot:specifiedRoot, and
  ^ot:unrootedTree
properties based on the use of the trees for synthesis study
lists in gcmdr commit 35bf307e72bed4f59724762dde4a12965abcea92