Bug: The type `PInvoke` conflicts with other types of the same name imported in multiple assemblies

[Lamparter]

Description

Using the Windows.Win32.PInvoke class when more than one Riverside.Win32.* package is referenced will cause the issue shown above.

Steps to reproduce

1. Create a class library
2. Add more than one package from this library
3. Try to use the Windows.Win32.PInvoke class
4. See the error

This also occurs when using the aggregate package (Windows.Win32), as this installs all the packages.

[Lamparter]

This could be fixed if the namespace could be customised, see microsoft/CsWin32#1312