Local shapefiles + acronyms

[DreaJulca]

Right now, they are stored in extdata. It may be more efficient in terms of library size (given the general < 5MB rule) and latency to use sysdata (via devtools::use_data()) for the shapefiles and add the acronyms to the Dydra repo. With that said, it may also be practical to just point to the location of the shapefiles for download by the user, or to include the acronyms in the sysdata file, and of course we could stick with the current approach (to be honest, however, I am leaning toward my first suggestion - dydra repo for acronyms, sysdata for shp).

[DreaJulca]

Also, the Metro-level shapefiles (USMSA, NUTSMetro) cannot be loaded:

Error in rgdal::readOGR(dsn = localPath, layer = "USMSA.shp") : 
  no features found
In addition: Warning message:
In ogrInfo(dsn = dsn, layer = layer, encoding = encoding, use_iconv = use_iconv,  :
  ogrInfo: all features NULL

(and of course, the NUTSMetro file does not exist).

To deal with this for the time being, I have temporarily suppressed metro-level shps.

[DreaJulca]

Partially closed: Shapefiles read in and stored in sysdata, need to decide on acronym storage