[Retros] Add units: 17th update (1RA)

[Mu-Tsun Tsai]

> 8/Ppp5/PNp5/1B6/P7/Pk6/pP1P4/2K5


That's a very nice structure, using the fact that the white king couldn't 
have moved to force another capture by the original f7 pawn.
Too bad I'm not capable of designing something like this yet.


Mu-Tsun