Update README for disabling intellisense
Update README for disabling intellisense

Fixes #430

nosami/xamarin-monodevelop-fsharp-addin,nosami/xamarin-monodevelop-fsharp-addin,fsharp/xamarin-monodevelop-fsharp-addin,fsharp/xamarin-monodevelop-fsharp-addin,Ming-Tang/fsharpbinding,Ming-Tang/fsharpbinding,fsharp/fsharpbinding,Ming-Tang/fsharpbinding,fsharp/fsharpbinding,fsharp/fsharpbinding