infer that game is from position if a FEN is given in the import

modules/importer/src/main/DataForm.scala

@@ -31,8 +31,10 @@ private[importer] case class ImportData(pgn: String) {
       def tag(which: Tag.type ⇒ TagType): Option[String] =
         tags find (_.name == which(Tag)) map (_.value)
 
-      val variant = tag(_.Variant).flatMap(v ⇒ Variant(v.value)) | Variant.Standard
       val initBoard = tag(_.FEN) flatMap Forsyth.<< map (_.board)
+      val variant = tag(_.Variant).flatMap(v ⇒ Variant(v.value)) | {
+        initBoard.nonEmpty.fold(Variant.FromPosition, Variant.Standard)
+      }
 
       val result = tag(_.Result) filterNot (_ ⇒ game.situation.end) collect {
         case "1-0"     ⇒ Result(Status.Resign, Color.White.some)

todo

@@ -64,4 +64,3 @@ edit board from play fen
 clickable mistakes list in analysis
 FEN/editor castle/enpassant https://github.com/ornicar/lila/issues/42
 stupid team forum slug http://ru.lichess.org/forum/team-4epa250h
-import PGN with FEN position without chess960 (handicap) (claymore on #chess)