Support for timestamps as x-axis scale

#### Is your feature request related to a problem? Please describe

Model monitoring is trying to show the number of predictions generated by a deployment within time intervals, and wants to use a histogram to do so. We are encountering a problem where we need to set x_min and x_max for an interval, but when the x axis is timestamp (string) this is not possible.

Example of timestamp x-axis:

#### Describe the solution you'd like

We would like support for timestamps for x axis

#### Describe alternatives you've considered

- conversion of timestamp to epoch, but this would not be user-friendly to display

#### Additional context

Workaround ideas welcome!