Add mod documentation in seven languages

manifest.json

@@ -3,7 +3,7 @@
   "name": "Trading",
   "version": "1.0.0",
   "author": "ct",
-  "description": "Shops: merchants defined as data (\"Kind\": \"shop\": what they sell, what they buy back and at which price) and a trade window of two inventories side by side, the merchant's goods and the player's bag, with a deal card between them. Money is an ordinary inventory item, the gold coin money/coin by default. Scenario action: trade.open shop=<id>.",
+  "description": "Shops as data and a trade window of two inventories: the merchant's goods on one side, the player's bag on the other, and money as an ordinary item.",
   "category": "gameplay",
   "sources": [
     "src/**/*.cs"