Add support for search by uid (#4876)

Signed-off-by: Andrew Thornton <art27@cantab.net>

templates/swagger/v1_json.tmpl

@@ -5203,6 +5203,12 @@
             "name": "q",
             "in": "query"
           },
+          {
+            "type": "integer",
+            "description": "ID of the user to search for",
+            "name": "uid",
+            "in": "query"
+          },
           {
             "type": "integer",
             "description": "maximum number of users to return",