upgrade to Scala 2.12

[claymccoy]

Code that depends on this library will be held back from upgrading to 2.12.

It looks like that would require:
• ditching spray which is already an issue #84
• updating akka to 2.4.14 which is already a PR #90 (except to the 2.12 version)
• updating scalatest
• updating json4s-native

[trbngr]

I've started a new repo that abstracts Http and JSON libs out of the way. It's taken care of everything in your list. But I used SBT instead of Maven (personal choice). It's far from complete at the moment, but all the hard work is done already. Just need to implement the rest of the client and akka helpers.

https://github.com/trbngr/elasticsearch-client-abstract

If everyone disagrees with SBT, I will continue development on my repo and come back to this repo with a PR.

Thoughts?

I wasn't a fan of how this was turning out. Alot of it had to do with all the cruft from json4s being baked into the core project. And to rip that stuff out safely, I needed some ADTs for the Api DSL. And that didn't work out.

So.........I created a new project.
https://github.com/trbngr/elasticsearch-http4s

The client Api is really small and easy to use.

You can implement any Http client you want. I currenlty have an akka-http client in the project. Not hard to add others.

You can implement any Json library support. I currently have a circe implementation.

I realize that my project is a drastic change from this lib. So with that, I'm just going to focus more time on it.

If you like it, though, please feel free to play with it and submit PRs.

Thanks for the start!

[rcoh]

We're finally tackling this in #158