Add a couple comments on breadcrumb config and early exit behaviors
Add a couple comments on breadcrumb config and early exit behaviors

getsentry/raven-js,getsentry/raven-js,miguelb/raven-node,getsentry/raven-js,BuildingConnected/raven-node,getsentry/raven-node,getsentry/raven-node,miguelb/raven-node,getsentry/raven-js