Library redesign

[blackheaven]

Following 0.19.0.0 release, a discussion started to rework a part of bloodhound structurally.

Things I have in mind at the time:

• [ ] Having a proper Request/Command type which would
  • Include supported versions (eg. Since '[7,2] or Between '[6, 5] '[8])
  • Include expected response type (do so with Reply and add a debug function)
  • Include relative path (instead of a monadic creation via joinPath)
• [ ] Splitting queries sum types to improve extensibility
• [ ] Having a Monad/Typeclass setting-up the ElasticSearch version

I think it would be a good start, but any idea/feedback is welcomed.

[blackheaven]

0.20.0.0 has been release, except:

• Type level versioning has been delayed since 8.x is not supported yet
• Query cannot be split since it should implement FromJSON