Implemented nuspec files and cleaned up a little

I created the 3 nuspec files to generate the nuget packages

To build make sure you built the solution in release mode and call the following statements in the corresponding project folder. (you can download nuget.exe from https://nuget.org/nuget.exe )

nuget pack XForms.Toolkit.csproj -Prop Configuration=Release
nuget pack XForms.Toolkit.Droid.csproj -Prop Configuration=Release
nuget pack XForms.Toolkit.iOS.csproj -Prop Configuration=Release

This will give you a set of nuget packages which you can push to the nuget.org feed. (see instructions here http://docs.nuget.org/docs/creating-packages/creating-and-publishing-a-package)

Regards,

Filip De Vos