added underscore and d3-chord-diagrams

Updated the list of required libraries to include d3-chord-diagrams and
underscore
initial creation

This file is a chart plug-in for RAW. It creates basic chord diagrams,
incorporating code from Steven Hall’s d3-chord-diagrams.
chord diagram stylesheet

this is required to display the correct look and feel for the chord
diagrams
dummy square matrix data for chord diagrams

this is sample data that forms a square matrix
img file for chord diagrams
updated for chord charts

added lines to point to chord diagram plugin, stylesheet,
underscore.js, and d3-chord-diagrams
updated diagram description

corrected note on input data… from n*n to n*(n-1)/2
added line to include debts sample data

added a line to the file to point to the new debts sample data that is
useful for the chord diagram