add object-store-aws test

[jrjdavidson]

small change to add object-store-aws test, also add example on how to use keys.

[gadomski]

I don't mind having a network-touching test, but I'd prefer it as a "regular" test (not a doctest) or an "integration" test (in a tests diretory) which will make it easier to skip/ignore later on if (e.g.) the network location breaks.

[jrjdavidson]

I don't mind having a network-touching test, but I'd prefer it as a "regular" test (not a doctest) or an "integration" test (in a tests diretory) which will make it easier to skip/ignore later on if (e.g.) the network location breaks.

Good point about network location potentially breaking.

It took me a little while to figure out how to pass the options to object_store ( i had to explore the object_store crate and try various keys) and thought having an actual working example in the docs might help someone in the future.

[gadomski]

Awesome, thank you!