message: Bump C# version to 8.0
diff: <SolutionDir Condition="$(SolutionDir) == '' Or $(SolutionDir) == '*Undefined*'">..\</SolutionDir>
  <RestorePackages>true</RestorePackages>
  <TargetFrameworkProfile />
  + <LangVersion>8</LangVersion>
  </PropertyGroup>
  <PropertyGroup>
  <StartupObject>TogglDesktop.Program</StartupObject>
  