Merge pull request #137 from lothrop/master

Added Microsoft.Bcl.Async to the list of supported Nuget packages.
Issue 138 - Added nuget references to  Microsoft.Net.Http  for iOS, Droid and Windows Phone.
Amended Nuget Packages config file.
Xamain Forms Labs Packages Config file updated.
Added OverwriteFiles to Scorchio.NinjaCoder.Xamarin.Forms.Labs nuget config
Shortened names f xamarin forms  nuget packages
Renamed MvvmCross plugins config file.
Added StyleCop to nuget packages config file
Changef stylecop to stylecop.msbuild in nuget packages config file.
Version 3.2.0