Added tests in EquaSetSpec to ensure FastEquaSet flatMap method return type is FastEquaSet.
Added tests in EquaSetSpec to ensure FastEquaSet flatMap method return type is FastEquaSet.

rfries/scalatest,rfries/scalatest,janekdb/scalatest,flicken/scalatest,gcberger/scalatest,SRGOM/scalatest,gcberger/scalatest,rahulkavale/scalatest,triggerNZ/scalatest,SRGOM/scalatest,rahulkavale/scalatest,matterche/scalatest,janekdb/scalatest,SRGOM/scalatest,flicken/scalatest,rfries/scalatest,SRGOM/scalatest,matterche/scalatest,gcberger/scalatest,triggerNZ/scalatest,triggerNZ/scalatest,triggerNZ/scalatest,matterche/scalatest,flicken/scalatest,janekdb/scalatest,janekdb/scalatest,gcberger/scalatest,rfries/scalatest,rahulkavale/scalatest,rahulkavale/scalatest,matterche/scalatest,flicken/scalatest