Create a vignette

[jeremystan]

Create a vignette for tidyjson titled "Introduction to tidyjson."

Assume the reader has:

• Limited knowledge of JSON
• Some experience with dplyr and %>%

Explain the key underlying principles of tidyjson:

• Turns arbitrary JSON into R data.frames
• Guarantees a deterministic structure
• Seamless with dplyr and %>%

Explain that data can come from multiple places:

• Public APIs
• Document oriented databases
• JSON over HTTP services

Demonstrate how it works with a few practical examples, then provide an overview of the key functionality.

[jeremystan]

Need to do the following:

1. Explain how tbl_json objects are structured
2. Expand the Data section to cover (a) included data, (b) various means of creating tbl_json objects
3. Update the verbs section to be consistent with the table
4. Use a real example (data included in package) in the strategies section

[jeremystan]

First draft completed!