Rename San Antonio, TX to Bexar County, TX and switch to ESRI shapefile source

San Antonio recently added an ESRI shapefile download for their address data. I switched to that since it seems like it would be preferred over the ArcGIS server. (I guess?)

I also switched the coverage to Bexar country since the city's data covers every city and unincorporated area in the county except for the military installations.

Unfortunately the currently download fails due to an SSL error because the server is failing to send an intermediate CA certificate. I sent them an email about the issue, so hopefully that will be resolved. If not I guess we will have to work around that somehow.