updated intro draft based on new brett comments, big improvement
updated intro draft based on new brett comments, big improvement

openconnectome/ocp-journal-paper,neurodata/ocp-journal-paper,neurodata/ocp-journal-paper,openconnectome/ocp-journal-paper,openconnectome/ocp-journal-paper,neurodata/ocp-journal-paper,neurodata/ocp-journal-paper,openconnectome/ocp-journal-paper