Log retry attempts

[renecouto]

I think it would be useful if the request attempt number was logged, at least in debug mode

[inyutin]

Thank you for your suggestion!

I'm added debug log for attempt number in v.1.1. Due to #7 aiohttp_retry==1.2 should be fine.

However, if you're planning to update I recommend v2.0. It is not compatible with previous versions, but it makes easier to specify all those retry options. You can find out new examples at Readme.md

I'm sorry for such a long time not responding.