CefSharp.Example updates for Chromium 31

A few changes to CefSharp.Example demo apps embedded HTML in celebration
of the Chromium 31 update
CefSharp3 WPF doc bopping

In CefSharp3 the CEF class is now named Cef. So let's use the same for
this very first intro for new users.
Also make it easy to find the NuGet Wpf package