Remove the 'fields' URL param from the REST spec.

We don't actually support 'fields' as a URL parameter.

Author: jtibshirani

rest-api-spec/src/main/resources/rest-api-spec/api/search.json

@@ -56,10 +56,6 @@
         "type":"string",
         "description":"The field to use as default where no field prefix is given in the query string"
       },
-      "fields": {
-        "type":"list",
-        "description":"A comma-separated list of fields to retrieve as part of each hit"
-      },
       "explain":{
         "type":"boolean",
         "description":"Specify whether to return detailed information about score computation as part of a hit"