Rework solution structure to allow more types of library projects (#196)

* Rename avalonia & wpf samples

* Rename rest of samples

* fix sample readme

* Fix compat util tests

* rename / move all src projects

* remove package lock files and move libC# again

* Add rust lib and cargo workspace

* Replace locksmith lib with new filelocksmith-rs library

* Deprecated type

* fix setup compile

* Use thiserror for error handling

* Rename some enums and formatting

* Add missing SHA256

* wip c++ library

* cpp wip

* alphabetize readme

* Try to get build working again

* Fix some conditionally compiled bits

* cross config should be in workspace root

* Fix PathHelper for new rust target dir

* Missed one old path to velopack.csproj

* remove obsolete coverage code

* testawareapp.exe no longer exists

test/TestApp/TestApp.csproj

@@ -15,7 +15,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\..\src\Velopack\Velopack.csproj" />
+    <ProjectReference Include="..\..\src\lib-csharp\Velopack.csproj" />
   </ItemGroup>
 
   <ItemGroup>