Fix build issue in the MonoDevelop add-in
Fix build issue in the MonoDevelop add-in

Add Makefile as a dependency of the generated project files.
This ensures that the project files are always regenerated
when the configure script is run

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