Support initial state "左七枚落ち", "右七枚落ち" as Kakinoki format

[gemmaro]

README.md says:

InitialPresetString = string 平手，香落ち等KIFでサポートされている手合情報

And "棋譜ファイルKIF形式 > ５．手合割" defines additional "左七枚落ち", "右七枚落ち."
So I think JKF should support them too.

[na2hiro]

2021/3/14 手合割に「左七枚落ち」と「右七枚落ち」を追加

Didn't know that. I'm going to add them

[na2hiro]

#54