Build Fix - set IntermediateOutputPath for each project

Resolves #11

So VS2012 will build projects in parallel whenever it can get away with it.

Currently 0.2.0 has a *teeny tiny* problem where the `net45` and `netcore45` outputs are actually the `wp8` build output. 

Why? Because without setting [`IntermediateOutputPath`](http://msdn.microsoft.com/en-us/library/vstudio/bb629394.aspx) explicitly, each build will use the same `obj\Release` folder - and each of the csproj files are in the same folder.

So I've made these values project-specific and bumped the version.

I hit this same problem in MahApps.Metro and the workaround was to make the dependency explicit so they don't build in parallel. That workaround was crap, so I need to do this over there as well.