Port changes from 3.20 to V4

[CharliePoole]

NOTE: Only issues that require porting are listed. In some cases V3 issues pertain to features, which are being dropped.

• Presence of a TEAMCITY_PROJECT_NAME environment variable makes builds fail if TeamCity service unavailable #1570 (not sure... may have been done as part of another fix)
• Eliminate BinaryFormatter #1354
• The nunit engine does not use the extension with the latest version if multiple versions are available #1678
• The filter "tests" truncates the provided value at the first closing parenthesis. #1680

[CharliePoole]

@nunit/engine-team

The unchecked items are all available to be worked on if you have time. I did #1354, which was blocking. FYI, I typically use a branch name of "port-nnnn" for the ports.

[CharliePoole]

This issue has been resolved in version 4.0.0-beta.1

The release is available on:
GitHub.
NuGet packages are also available NuGet.org and
Chocolatey Packages may be found at Chocolatey.org