This patch:
* changes the weapon of cart and gaul infantry swordmen to (Celtic) `csword`, because all other Celtic swordsmen (cavalry, champions, heroes, ptol mercenaries) use it already and the `spatha` is a Roman cavalry sword;
* changes the weapon of athen cavalry swordsmen to `falcata` (kopis/makhaira), a chopping sword, because ancient sources (e.g. Xenophon) emphasize cavalry used that, not a `xiphos` (similar to gladius or akinakes), a short stabbing sword, unsuitable for horsemen