Release the CLI tool

**Is your feature request related to a problem? Please describe.**
The Samples project, XrmToolbox plugin, and CLI tool are three ways to use the engine. Of course, we could use the nuget package in our own projects as well. Personally, I like the CLI since it's up to date with the latest engine and I could use it outside the context of the Samples project. Unfortunately, it means pulling the latest codebase and building manually.

**Describe the solution you'd like**
Build and publish the CLI tool as a [dotnet global tool](https://docs.microsoft.com/en-us/dotnet/core/tools/global-tools) with the latest version of the engine.

It is also worth adding a small section in the README on the tool although it should be self documenting (via -help).