adds response_format to local/devel Format-filter config file

data-discovery/config/formatresponsefilter.properties

 
+response_format=application/x-votable+xml
+# response_format=application/x-vlkb+xml
+
 # used to retrieve extraCards to add to FITS_header (VLKB-only)
 surveys_metadata_abs_pathname=/srv/vlkb/surveys/survey_populate.csv