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. 
there does not appear to be an identicial log level setting between java and clr log settings. that is why a mapping is introducted here.