Please use version bytes for bech32 xpub

[shivaenigma]

The xpub generated by bech32 bitpay wallet is currently starting with prefix xpub

This creates multiple problems:

• Incorrect balance display in watch only wallets / blockexplorer using xpub
• Mismatch of xpub with other wallets like electrum, trezor, samouri
• Incorrect address derivation from xpub - used by Merchant utilites like BtcPay

References

https://github.com/bitcoin/bips/pull/680 https://electrum.readthedocs.io/en/latest/xpub_version_bytes.html