Add support for Visual Studio "Enable full solution analysis"

[Gav-Brown]

In Visual Studio you can specify Options\Text Editor\C#\Advanced\Enable full solution analysis. With this on VS will run all its Code Style rules on all files in the solution whether they are open or not.

However, when using an .editorconfig file, instead of the VS Code Style rules they replace, the rules only get applied to the currently open files.

Could we add support for and respect this option?

This may be a VS issue rather than EditorConfig?

[ffes]

This may be a VS issue rather than EditorConfig?

It sure sounds like that

[Gav-Brown]

@ffes Do you know if this should go on the dotnet/roslyn board?