Suggestion: (Flagwar) Enable PVP in a set area around a flag

[Bingzhe0904]

Please explain your feature request to the best of your abilities:

Instead of forcing PVP and explosion in the chunk a flag is placed on, it would be really nice to open up the battlefield by forcing PVP and explosion in a set area around the flag. The forced explosion and PVP would be similar to what Siegewar has, except the radius would be generally smaller.

Thanks for considering this suggestion!