Porting Savina benchmarks to Akka-GC

[dplyukhin]

Can we port benchmarks from the Savina suite to our library? This is the first step towards Issue #2.

• [x] Get the Savina suite running on your machine. Report: How do you set it up? How do you run a benchmark?

• [x] Port one of the simpler benchmarks, like fibonacci, to Typed Akka. Report: Is the performance comparable to the original implementation?

• [x] Port the benchmark to use Akka-GC. Report: How does the performance compare? What do you think might be a bottleneck?

[dplyukhin]

Done! The benchmarks are on a separate repo.