Adding NLog docs
Adding NLog docs


Former-commit-id: e7aa6c70f8a57cacad49e79a004705fbd400f3b6
MassTransit/MassTransit,jacobpovar/MassTransit,phatboyg/MassTransit,MassTransit/MassTransit,phatboyg/MassTransit,jacobpovar/MassTransit,SanSYS/MassTransit,SanSYS/MassTransit