Code analyzer to check the type passed to ProvideOptionDialogPageAttribute and ProvideProfileAttribute

[reduckted]

Related to #279.

Using the wrong type in ProvideOptionPageAttribute seemed like a good candidate for a code analyzer to catch the problem early and to suggest a fix (where possible).

CVST003 will detect the wrong type being provided to ProvideLanguageEditorOptionPageAttribute, ProvideOptionPageAttribute and ProvideToolboxPageAttribute (they all expect a DialogPage)

CVST004 will detect the wrong type being provided to ProvideProfileAttribute (it expects an IProfileManager, which DialogPage implements).

Both diagnostics have a code fix that will suggest changing the type to a type that is nested within the type nested type that inherits/implements the correct type. For example, give this:

internal partial class OptionsProvider
{
    [ComVisible(true)]
    public class GeneralOptions : BaseOptionPage<General> { }

    [ComVisible(true)]
    public class OtherOptions : BaseOptionPage<Other> { }
}

and providing an options page like this:

[ProvideOptionPage(typeof(OptionsProvider), nameof(TestExtension), "General", 0, 0, true)]

The code fix will suggest:

• Changing typeof(OptionsProvider) to typeof(OptionsProvider.GeneralOptions)
• Changing typeof(OptionsProvider) to typeof(OptionsProvider.OtherOptions)

Demo:

[ErikEJ]

Sweet!

[madskristensen]

That's awesome. Thank you