Display multiple milestone dots on timeline report

Currently, the custom roadmap only supports a view with either a single data point (milestone dot) or two data points (bar w/ start and end dates).

This hinders us from being able to visually, at a glance, see target milestones between start and end dates of an initiative instead of a pivot report.

It would be really helpful to be able to mark "milestone" dates within a bar, so you can have, for example, a start and end bar, with more than one dot within that bar showing other critical target milestones.