[MINDEXER-166] Propose UrlResource with retry logic

[sixcorners]

Don't merge this as-is.

Does anyone think it would be a good idea to add a UrlResource that has retry logic?

[cstamas]

Am not convinced. As app integrating indexer should (and could in app specific) way wrap any OOTB (or implement new) with al lthe logic it needs/has.... Otherwise we end up with some super-duper-configurable-fit-for-all retry logic, which I'd rather avoid.