add readme and change some scripts

scripts/fix_image.ts

@@ -0,0 +1,23 @@
+import GameCommon from '../src/common/GameCommon'
+import { logger } from '../src/common/Util'
+import GameStorage from '../src/server/GameStorage'
+
+const log = logger('fix_image.js')
+
+function fix(gameId) {
+  GameStorage.loadGame(gameId)
+  let changed = false
+
+  let imgUrl = GameCommon.getImageUrl(gameId)
+  if (imgUrl.match(/^\/example-images\//)) {
+    log.log(`found bad imgUrl: ${imgUrl}`)
+    imgUrl = imgUrl.replace(/^\/example-images\//, '/uploads/')
+    GameCommon.setImageUrl(gameId, imgUrl)
+    changed = true
+  }
+  if (changed) {
+    GameStorage.persistGame(gameId)
+  }
+}
+
+fix(process.argv[2])