signed net35, net40 and net45

signed desktop profiles

This PR will fail as NLua.dll tries to reference non-signed assemblies.

You will need to merge these https://github.com/NLua/KeraLua/pull/9 and https://github.com/NLua/KopiLua/pull/12 first and update the git submodules so it references the signed assemblies before you merge this in.