Extracts the lat and long for each address from authors_cleanSource:
authors_georef This function takes the final author list from
refine_authors, and calculates the lat long of the addresses.
It does this by feeding the addresses into data science toolkit.
In order to maximize effectiveness and mitigate errors in parsing addresses
We run this multiple times creating addresses in different ways
in hopes that the google georeferencing API can recognize an address
1st. University, city, zipcode, country
2nd. City, zipcode, country
3rd. city, country
4th. University, country
name of column in quotes where the addresses are
The output is a list with three data.frames
addresses is a data frame with all information from
refine_authors plus new location columns and calculated lat longs.
missing addresses is a data frame with all addresses could
not be geocoded
addresses is a data frame like
the missing addresses are gone.