Regression introduced by abbd62ac:
- Since abbd62ac, all map metas are loaded at server startup.
- In `ctf_match.create_teams`, `map.teams.pos` is passed to `ctf_flag.add`.
- As tables are passed by reference, properties added to `ctf.team("team_name").flags[i]` are also added to ctf_map.map.teams.
- This means that the next time this table is passed to `ctf_flag.add`, this table would already contain the `claimed` property, that holds the name of the player who last claimed the flag at this pos, and the name of their team.
This is fixed by simply passing `map.teams.pos` to `ctf_flag.add` using `table.copy`
Fixes regression introduced by abbd62ac, which calls `load_map_meta` for all maps right at server startup, instead of calling it per-map for every new match.
