Add README and appveyor to solution

Author: angularsen

RoslynAnalyzers.sln

@@ -11,6 +11,12 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AssignAll.Vsix", "AssignAll
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SampleConsoleApp", "SampleConsoleApp\SampleConsoleApp.csproj", "{50FFCAEA-07D5-493E-8904-DEE6A7D9BE0D}"
 EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Files", "Files", "{D4A0A564-543B-4220-8194-F1E7447A4E2D}"
+ProjectSection(SolutionItems) = preProject
+	appveyor.yml = appveyor.yml
+	README.md = README.md
+EndProjectSection
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU