Allow plotting point data

[kwinkunks]

Not sure what the interface should look like, but now that welly can handle point data, it feels like we should make it easier to plot as points.

Here's an example, along with a striplog (which we should also play nicely with).

[Michael-P-Crisp]

Hi, is there any update on this?

In fact, I'm having difficulty finding information in the documentation on how to handle point data, let alone plot it.