Include "recipes" in vignette

[seandavi]

• histogram of base counts (in 0f6ff0b)
• filter samples by bioproject (in 0f6ff0b)
• filter samples by region (in 0f6ff0b)
• summarize counts to "level"
• filter samples by bug presence

Add additional use cases below.

[vincerubinetti]

Recipes were also added to the website here. Ping me if/when you add more, or feel free to edit that file yourself.