[meaghanlewis]

This PR removes:

• The test_script block from appveyor.yml and uses Appveyor's auto testing mode instead
• The Appveyor flag from scripts\test.ps1
• The package NUnit.Extension.AppVeyor.NUnit3ResultWriterand all references to it

Closes #1289

[grokys]

The latest build on master ran 806 total tests, but this PR is running 804 total tests (Seems to be running 4 less tests in UnitTests and 2 more tests in TrackingCollectionTests)

In the case of UnitTests, this seems to be caused the ignored GraphsNavigationItemTests.TheExecuteMethod test. This test was appearing in the list of tests before, but the status was gray indicating that it was ignored, whereas now the test isn't included in the list. The test has 4 TestCases so this explains that.

In the case of TrackingCollectionTests; MultipleSortingAndFiltering and OrderByDoesntMatchOriginalOrderTimings are now being run where they weren't before. These two tests are marked with Category("Timings"), which was marked as being ignored before. You can use appveyor.yml to ignore these files.

[shana]

Should I update scripts\test.ps1 and remove the Appveyor flag since it seems we'll only be using this script locally now?

Yup, and you can also remove the NUnit.Extension.AppVeyor.NUnit3ResultWriter package from our nuget solution (in VS, Tools -> Nuget Package Manager -> Manage Nuget Packages for Solution and then in the Installed tab find the package and uninstall it from all projects that have it installed). After that, you can delete the NUnit.Extension.AppVeyor.NUnit3ResultWriter.0.1.0.nupkg package from lib/ 😄