Add command to copy flags from a region

[Z0rdak]

Description

To make setting up regions more easy it would be nice to be able to copy flags from existing regions.

Todo

• [x] Add command to copy the flags from a local region to another
• [x] Add command to copy the state from a local region to another
• [x] Add command to copy the players from a local region to another
• [x] Add command to copy the flags from a dimensional region to another
• [x] Add command to copy the state from a dimensional region to another
• [x] Add command to copy the players from a dimensional region to another
• [x] Regions suggested should only be owned regions, to prevent copying flags from foreign regions (this would leak to added flags of regions from other players)
• [x] Add language keys

[Z0rdak]

Follow up: Extend copy command to other properties like

• state
• affiliations
• ...

[Z0rdak]

Copy teams and affiliation won't be added with this issue. This will have to wait until LuckPerms integration is implemented