message: Support nano prefix in addition to xrb prefix
  fixes
diff: @@ -215,8 +215,18 @@ function getPublicAccountID(accountPublicKeyBytes) {
  }
  function getAccountPublicKey(account) {
  - if ((!account.startsWith('xrb_1') && !account.startsWith('xrb_3')) || account.length !== 64) throw new Error(`Invalid NANO Account`);
  - const account_crop = account.substring(4,64);
  + if (account.length == 64) {
  + if(!account.startsWith('xrb_1') && !account.startsWith('xrb_3')) {
  + throw new Error(`Invalid NANO Account`);
  + }
  + } else if (account.length == 65) {
  + if(!account.startsWith('nano_1') && !account.startsWith('nano_3')) {
  + throw new Error(`Invalid NANO Account`);
  + }
  + } else {
  + throw new Error(`Invalid NANO Account`);
  + }
  + const account_crop = account.length == 64 ? account.substring(4,64) : account.substring(5,65);
  const isValid = /^[13456789abcdefghijkmnopqrstuwxyz]+$/.test(account_crop);
  if (!isValid) throw new Error(`Invalid NANO account`);
  