Add percentiles and newer literature

[bransonf]

@chris-prener

Table of percentiles in results/ntile_distances.csv
Short Annotated Bib in docs/Annotated Bibliography of Geocoding Resources.docx

The table should be an easy copy and paste into the existing paper and the annotated bib should provide a sufficient number of papers to satisfy the commenters on newer literature.
In short:

• Common errors associated with geocoding
• Necessary match rates for statistical reliability
• The influence of geocoding error on ecological and criminological studies

Let's follow up on Basecamp about what else needs to be done before resubmitting.

Thanks!