main/pure-maps: enable tests and take ownership

Edit: Seems like the failing tests require API keys. Not sure how this should be dealt with. Pure Maps' maintainer thinks we're better off not just running them, which definitely is an option.

There are currently some test failures which I've yet to look at, but most tests do work (and pass)!

As for the added patches, one already is in master and the other I made a pull request for on GitHub: https://github.com/rinigus/pure-maps/pull/508