mapping key update and State dept fix

1. added processing time stats to both agency and offices to increase coverage for offices that have the same name as their agency 
2. updated the mapping key for both foia.gov/data and foia contacts. This will help query info from the foia contacts xls when we need it 
3. minor changes to the processing time scraper to work with new mapping key 

Should fix 18F/foia-hub/issues/321 and any other instances similar to it and replaces 18F/foia/pull/79
Removing empty values