Pgns longer than the ply limit are allowed to be imported

[johndoknjas]

I had a chapter that was at the ply limit, so to test I copied its pgn text and typed in one more move at the end. Importing this pgn in a new chapter was then allowed.

There was also a case where I was at the ply limit, so I went a few moves back and deleted the mainline (as well as a short variation). I then was able to make a number of moves from that point without being stopped.