Set up citation format for book

[larapclark]

Set up formatting for citations throughout the book:

• [x] Select a style (Chicago)
• [x] Add BibTex reference file
• [x] Set up style for book
• [x] Edit the existing draft chapters (add links to references in BibTex file):
  • [x] Spatial Data Analysis
  • [x] NASA EarthData Download
  • [x] Link to Census
• [x] Update new chapter template