Add .NET 4.5 and Portable Profile 259 builds while continuing support for .NET 4.0 and dropping support for Silverlight 4

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Although binding redirects (see Issue 78) can be used to fix any versioning 
issues using a version of Unquote referencing FSharp.Core v4.0 in an F# project 
referencing FSharp.Core v4.3, a .NET 4.5 build would eliminate any chance of 
confusion. Like Issue 88, this would appear in some future "Unquote 3.0" 
release.

Original issue reported on code.google.com by stephen....@gmail.com on 28 Apr 2012 at 2:32