Remove unused scatter plot code

[ian-noaa]

Problem

In dtcenter/MATScommon#27, it was discovered that there is a good amount of unused scatter plot code in MATScommon.

Solution

The scatter plot code should be removed so that we don't need to maintain dead code.

No Go's

Describe any features or behaviors that have been considered and rejected as out of scope for this project

Tasks

Describe discrete tasks that need to be done to complete this project

• Task 1
• Issue link
• etc...

[mollybsmith-noaa]

All of Molly's in-use scatter code is for the plot type matsTypes.PlotTypes.simpleScatter

[github-actions]

This issue is stale because it has been open 90 days with no activity.