Use web service to estimate sats per byte

[mgravitt]

Here are some services we can use to retrieve a current fee estimate:

https://www.lopp.net/bitcoin-information/fee-estimates.html

List of many of them:
https://b10c.me/blog/003-a-list-of-public-bitcoin-feerate-estimation-apis/

This one returns JSON:
https://bitcoiner.live/api/fees/estimates/latest