Plot order

[sbfnk]

Description

This PR closes #783.

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[jamesmbaazam]

@sbfnk Unrelated to this PR but two questions/comments on the plotting method:

• Why is cumulative TRUE by default? I think when we have an uncertain distribution, the plot is quite busy. This leads to my next comment:
• I would suggest using color instead of line types to differentiate between pmf and cmf. Since there are only two levels, the color aesthetic plays nicely with the current default of "cumulative = TRUE" for uncertain distributions.

[sbfnk]

Thanks @jamesmbaazam - please approve the PR if good to merge.