Ahodges/doc/doc1119

@shnayder @WatsonEmily @dsjen @srpearce @stroilova here's the initial draft for the gender demographic data. I don't have access to real data yet, so can't quite finish up the screen-shot-and-its-interpretation piece. (Suggestions on a good illustration welcome)
The histogram does not include data for students who do not provide a year of birth at registration.