[DC 2016] "Washington, D.C." -> "Washington, DC"

Prevailing local style is not to use periods in DC.

data/events/2016-washington-dc.yml

@@ -1,6 +1,6 @@
 name: 2016-washington-dc # The name of the event. Four digit year with the city name in lower-case, with no spaces.
 year: "2016" # The year of the event. Make sure it is in quotes.
-city: "Washington, D.C. " # The city name of the event. Capitalize it.
+city: "Washington, DC" # The city name of the event. Capitalize it.
 friendly: "2016-washington-dc" # Four digit year and the city name in lower-case. Don't forget the dash!
 status: "current" # Options are "past" or "current".
 startdate: 2016-06-08 # The start date of your event, in YYYY-MM-DD format. Leave blank if you don't have a date yet.