Cross compile to 2.12

[lustefaniak]

Fixes #11

This is ready for library project.

For 2.11 it contains Spray and Akka-HTTP endpoint, for 2.12 only Akka-HTTP.

I'm not sure what should be done about demo project. I think best approach would be to move that project into separate repository. If that is not an option, similar approach as in library could be used and demo could be ported to akka-http.

There are still some deprecations about using JavaConversions in ProtoBufFormat, but changing it makes code a little bit less readable. I think it should be done using JavaConverters and breakOut to reduce allocations, but can happen in next PR.

[lustefaniak]

sbt-doge skips demo from 2.12.2 build, all should be fine now.

[coveralls]

Coverage increased (+0.4%) to 88.772% when pulling 77591d6 on lustefaniak:cross-compile-to-2.12 into 3b4a578 on MonsantoCo:master.

[coveralls]

Coverage increased (+0.4%) to 88.772% when pulling 5af088f on lustefaniak:cross-compile-to-2.12 into 3b4a578 on MonsantoCo:master.

[lustefaniak]

Hey @sattvik, do you think there is chance to get that merged and released? We are using 2.12 build in our applications for 2 months already and all is working fine. It would simplify our life if that was released upstream as now we are including copy of this codebase as module in sbt.

[bzumhagen]

Any chance we can get this merged now? Looks like it's approved?

@lustefaniak, @ElfoLiNk

[lukasz-golebiewski]

@ElfoLiNk What is preventing this PR from being merged?

[lustefaniak]

Kamon 1.0 has now Prometheus support, so probably there is no point maintaining this.