Deploy windows notification script to windows target only

[JanVargovsky]

Probably just add condition to Resources directory (Lib.csproj) - there are only windows resources right now and its pointless to deploy them on other platforms.

I personally tried to use some built-in properties (RuntimeIdentifier/RuntimeIdentifiers/TargetPlatform ...) during build but they are ignored afterwards (read that explicitly in the log).

Dont wanna introduce custom property for this since it would still require mechanism what OS you are using during development or do we even care if there is a small build overhead that is not necessary for other platforms except Windows?

[Bobris]

It could be fixed in Releaser project to delete unneeded files before zipping.