[SAM] Improve Iaijutsu and Ikishoten features

[Gakai]

• Iaijutsu:
  • Handle Kaeshi: Namikiri correctly
  • Add Goken checks to Tsubame Gaeshi handling (would not apply at all previously)
  • Keep Shoha on Iaijutsu after Kaeshi use (not only if weavable)
• Kyuuten/Shinten: Add option to include Zanshin after Senei/Guren
• Ikishoten: Add option to include Shoha before Ogi Namikiri

@Akechi-kun, could you check if these adjustments are appropriate? I'm trying my hand at my first PR here :)

[Akechi-kun]

I pushed a PR to your fork that keeps the templating more in line of how we usually do our Features tabs.. aside from that this is a good addition 👍