Fixed SL5 compilation

Aligned version number with the rest of ServiceStack and added missing file
links and excluded few blocks that can't compile in Silverlight 'mode'.


Demis, could you please let us know when is the next version coming out (pushed to NuGet)? I ask because I specifically fixed the SL5 build so that my company can actually use the SL 'port' of ServiceStack, the one currently on NuGet should be considered broken because the project ServiceStack.Interfaces (for SL5) is missing a crucial interface (IReturn) so the library to share contracts between the server/service and client **cannot** be built (for SL5) at all.

If you have any questions about the pull request, do not hesitate to contact me.

Thanks for all the hard work in making ServiceStack, it really is appreciated!

P.S. This is my first (OK, technically _second_ ;) since I have sent one almost identical to this one for ServiceStack.Text minutes ago) pull request, I apologize if I did something incorrectly, be glad to correct, just let me know. Cheers!