Fixed ARM/x64 configurations for TeamCity (v3.1), Mac components, nuspec

A couple changes in the ARM and x64 build configurations so that TeamCity CI can build the x64 and ARM sqlite plugin for Windows Store. I guess this becomes obsolete soon. Followed with adding some Mac components to the main solution.

I played around with updating nuspec for Profile 158 and WP8 changes, but this needs some review. I temporarily stuck the Mac stuff in lib/MonoMac (my goal is to be able to reach Mac from nuget in the Community Sqlite repository). However, because Mac always picks up from lib/net45 for nuget, I wonder if it shouldn't be a whole different nuget package that has the Mac components. Probably should be.