Updated OneCall API to v3.0

[JakeThomson]

OpenWeatherMap deprecated their OneCall v2.5 endpoint (#404), upgrading to use v3.0 instead.

[kmcnellis]

+1

[csparpa]

Hi I'm not able to test the PR locally, I trust you @JakeThomson have done it and PyOWM is now working again with the free tier API keys

[csparpa]

Also @JakeThomson thanks for this

You've patched the master branch, pls merge your changes also on the development branch if you have the possibility
Thanks again!

[JakeThomson]

Also @JakeThomson thanks for this

You've patched the master branch, pls merge your changes also on the development branch if you have the possibility Thanks again!

No problem, I had a look at this but it seems your master/develop branches are out of sync with each other and there are conflicts that I do not have the time to look into I am afraid.

@csparpa I was however wondering if we would be able to see a release for this change? I am having issues with my CI by pointing to the specific commit in my requirements.txt