akka-http-core for merge

This is the latest state of akka-http-core:

- Everything wired up properly against current akka-stream
- All tests green
- `test:run` gives you an HTTP server on port 8080 to play with

After merge these things are still missing for M1:

- Merge of Java API (basically ready but not yet part of this PR)
- client-side request rendering / response parsing (in progress)
- docs (in progress)

Normally yes. However, quality values in HTTP are not normally used for any kind of calculation. All we do is sort them.
And here we simply compare against the constant `1.0f`, which can be properly represented as a float.
So, in this particular case we should be fine.
However, I fully agree with you that any equality test between floating point numbers should ring alarm bells.