Merging reef-bridge into master

This includes all CPP code and bridge framework we built for .NET interop. 

Note that msbuild is required to build the .NET/CPP part of reef-breidge project. However, that will only be triggered when -PBridge profile option is used. Normal mvn build will simply skip the .NET/CPP codes. 
We don't have to. This is just the default fileds generted by VS. I will clean things up and leave only "non-empty" fields.