Alex Valuyskiy

- [x] Update to .NET 5 - [x] Update Scala benchmarks to Scala to 2.13 - [x] Update Akka to 2.6.x - [x] Update Akka.NET to 1.4.x - [x] Update...

- [x] EntifyFramework 5.0 counters - [ ] Make `AspNetCoreListenerHandler` - production ready - [ ] Make `EntityFrameworkListenerHandler` - production ready - [x] Update IdentityServer metrics - [x] Update EasyCaching...

What have done - Converted all projects to MSBuild 15 csproj files - Added `netstandard1.5` to `Zipkin.Core` and `Zipkin.Core.Tests` - Changed `build.fsx` What is not part of this PR -...