[Toolkit] Add IContentReaderFactory to IContentManager to allow dynamic ContentReader association based on type. Allow to load the same asset with different type (like Content.Load<Image> and Content.Load<Texture2D>). Make ContentManager more robust to null arguments.
[External] Add dependency to YamlDotNet fork from https://github.com/xoofx/YamlDotNet
[Toolkit.Yaml] Add new SharpDX.Toolkit.Yaml project that allows to load Yaml files directly into .NET object using the ContentManager.
[Toolkit] Fix compilation on Win8/WP8