Added missing d3 layout library
Added murder chart

Currently data is not from murders, it's just random test data.
Added real murder data

Displaying murders by location grouped by day.
Next step is to make the groupings selectable.
Made chart data grouping selectable
Removed option for stacked bar chart
Improved chart select style
Modified chart colours
Capitalised select options for data groups
Merge pull request #40 from kennib/diagrams

Diagrams