added population numbers for 2012 based on 2011, adjusting crime rate to reports per 100,000 residents
using jenks natural breaks (thanks @tmcw) for all map category cutoffs
appending category name to slug for disabmiguation, no longer associating intervention locations to datasets, moved legend positon on map
Merge pull request #59 from datamade/master

Jenks cutoffs, dataset disambiguation, 2012 population