Clone BCs and SDTM Specializations #83

As A BC and DSS curator, I would like to be able to copy an existing BC or Specialization and clone it. This would entail changing the group level information but making use of the set of DECs and Variables which can be tweaked. Another way to achieve a similar thing would be to select from Domain specific DEC templates for BCs and from Domain specific SDTM variable templates for DSS. These would be supersets and would need to be tweaked to fit the topic.