VS: add support for .NET references with hint paths
In the current implementation only .NET references without paths can be added. In addition all references must be given as a single property value, i.e. as a colon separated string.
This patch enables adding .NET references like this:
set_target_properties(target PROPERTIES VS_DOTNET_REFERENCE_MyAssembly "C:/path/to/my/assembly.dll" VS_DOTNET_REFERENCE_MyNextRef "myNextRef.dll" )
In addition the boolean target property
VS_DOTNET_REFERENCES_COPY_LOCAL is introduced which can be used to disable copying of the hint-referenced assemblies to the output directory (non-hint references are assumed to be system/.NET framework references which are never copied afaik):
set_target_properties(target PROPERTIES VS_DOTNET_REFERENCES_COPY_LOCAL OFF )
While copying of referenced assemblies can be set for each assembly individually in Visual Studio, the target property toggles for all referenced assemblies. I think this makes handling things easier, otherwise we would have to introduce additional target properties like
VS_DOTNET_REFERENCE_COPY_LOCAL_<refname> and set them individually.