Fix for EF issue 1109 - removing Microsoft.DataAnnotations nuget package

@bricelam @yishaigalatzer 

Replacing dependencies with direct dependencies on the underlying packages/assemblies.

See https://github.com/aspnet/EntityFramework/issues/1160.
You're right. It resolves fine without that. Plus I chatted it over with @bricelam and he's fine with the non-versioned line. Will remove.