Add support for Windows Runtime

This commit does not make any changes to the NuGet package.

The Options.WinRT project file contains only links to the existing
Options code. Support for F# was removed, as it does not exist in
WinRT. Similarly, support for serialization in NoneException was
removed.

This commit also updates the solution file to 2012.
Merge pull request #3 from JustinPierce/options-winrt

Support for WinRT
Bumped version. Added Justin as an author.
Removed packages from repo
Updated NuGet
Build multi-framework package
Support for Windows Phone 8
Remove spurious PlatformTarget in WP8 project
Version bump for WP8 bug fix
Support for asynchronous operations.

PowerShell script to ease the pain of building Windows Phone :shit:.
Version bump