Tinker, ensure plots render correctly

[eroten]

• [ ] interpretive alt text for all plots, including data source
  • [ ] 3 sentences: 1 descriptive, 1 interpretive, 1 broader point or contextual information
• [x] figure captions in consistent place
• [ ] plot titles descriptive and interpretive
• [ ] data source within plotly caption
• [x] set of PNG plotly plots without headings
• [ ] consistent colors
• [ ] group propane and kerosene into liquid stationary fuels