docs: public static BoxConfig readFrom(Reader reader) throws IOException {
          JsonObject config = JsonObject.readFrom(reader);
          JsonObject settings = (JsonObject) config.get("boxAppSettings");
          String clientId = settings.get("clientID").asString();
          String clientSecret = settings.get("clientSecret").asString();
          JsonObject appAuth = (JsonObject) settings.get("appAuth");
          String publicKeyId = appAuth.get("publicKeyID").asString();
          String privateKey = appAuth.get("privateKey").asString();
          String passphrase = appAuth.get("passphrase").asString();
          String enterpriseId = config.get("enterpriseID").asString();
          return new BoxConfig(clientId, clientSecret, enterpriseId, publicKeyId, privateKey, passphrase);
      }