QC: Review and Update Stats Vignette

[mattroumaya]

QC Details

• If time permits, review and update vignette as needed.

[mattroumaya]

• Summarize funnel plots first at a high level
  • "capsule" summary that any statistician can read in < 1 minute and know what we're doing in Gismo
  • Discussion about other stats methods will probably be confusing for the current Gismo implementation
  • ~two paragraphs explaining the defaults
  • think about something we can copy/paste for a training slide, e.g., z-score, overdispersion, general summary

[mattroumaya]

@jwildfire and/or @gwu05 to review the PR for this issue.

[mattroumaya]

Closed via #1126