Add time range selection to study page KM plots

[alisman]

A la the scatter and bar charts on study page, we want the user to able to drag select an x range of the chart and apply this as a filter on SV. This should be possible with the existing clinical data numeric filters.

Note that there are multiple kinds of km plots, one for each different type of related clinical data. You will find some code to detect these types and create the corrresponding charts.

Also, @dippindots has recently introduced "binning" as optimization to km plots with a lot of data. Normally the x axis is in days, but when there's a lot of data, we do it by month. You will need to make sure that your selection takes this into account. May or may not be simple.