Maybe a little late, but still. I had the same problem and you were looking for the source code for this (because it used to be: pointDot: false, which no longer works)
There are two ways to do it now:
Use parameters (this is in the nnick.github Chartjs and Search point.radius documentation)
options: { : {point: {radius: 1, hitRadius: 1, hoverRadius: 4}} }
data: {
datasets: [{
radius: 0,
: : 0