message: use map to convert int to WalletHandle
diff: @@ -220,10 +220,7 @@ pub fn get_opened_wallet(ctx: &CommandContext) -> Option<(WalletHandle, String)>
  }
  pub fn get_opened_wallet_handle(ctx: &CommandContext) -> Option<WalletHandle> {
  - match ctx.get_int_value("OPENED_WALLET_HANDLE") {
  - Some(value) => Some(WalletHandle(value)),
  - None => None
  - }
  + ctx.get_int_value("OPENED_WALLET_HANDLE").map(|val| WalletHandle(val))
  }
  pub fn set_opened_wallet(ctx: &CommandContext, value: Option<(WalletHandle, String)>) {
  