Switch to/add other weather providers

[nmlorg]

Would be nice to change the weather provider to https://openweathermap.org/ instead of the US Gov Weather as it covers weather world wide and has a lot of APIs to help developers.

It is also used in many open sourced weather apps.

Originally posted by @realmain in #80 (comment)

[nmlorg]

60 requests per minute will probably be okay, but it looks like they only offer 3-hourly forecasts over 5 days in the free tier (versus 1-hourly over 10 days from weather.gov), and have a license with an attribution clause for what would ideally be public-domain data :/

I'll poke around more with it once we've gotten the behavior/UI a little firmer! (And/or do you want to look into how it could work?)