Neo 3 Preview 2 Support

This preview adds Neo 3 preview 2 support for Neo Express.

Note, this preview release is using a temporary naming scheme to differentiate it from the production Neo-express release. The package is named Neo.Express3 and the tool is named nxp3. This naming allows developers to install both the production and insider releases of Neo-express at the same time. The package and tool names are temporary and will change before final release.

To install this release of Neo-Express, download the Neo.Neon3 package associated with this release, open a command prompt, change to the directory where you downloaded the package and execute the following command:

> dotnet tool install -g Neo.Express3 --add-source . --version 1.2.1-insiders