[Feature request] Add custom change option to SEND menu

[openoms]

from ./sendpayment.py -h

  -u CUSTOMCHANGE, --custom-change=CUSTOMCHANGE
   specify address to receive change , by default use in-wallet address.

[openoms]

Warning when using the option:

You are attempting to send change to a custom change
address. Change outputs are usually directly linkable to
your CoinJoin inputs, and incautious combination of
custom change UTXOs can catastrophically compromise
your CoinJoin privacy, especially if those UTXOs are from
different mixdepths.

Are you sure you know what you're doing? (y/n):