Add Gomoku arena

[Muhtasham]

Standard gomoku per wikipedia (not freestyle):

• 15×15 board
• Black plays first
• Exactly 5 in a row wins
• Overlines (6+) do NOT win

[john-b-yang]

Awesome stuff, thanks so much @Muhtasham! Code works very well. In the gomoku repository, I added

• per-game logging, this is helpful so a competitor can actually see how a game went
• a visualizer

Thanks so much! Merging 🚀

[john-b-yang]

LGTM!