MINOR: uri_normalizer: Add a `sort-query` normalizer

This normalizer sorts the `&` delimited query parameters by parameter name.

See GitHub Issue #714.
diff --git a/src/http_act.c b/src/http_act.c
index 3751b00..1480563 100644
--- a/src/http_act.c
+++ b/src/http_act.c
@@ -250,6 +250,23 @@
 
 			break;
 		}
+		case ACT_NORMALIZE_URI_SORT_QUERY: {
+			const struct ist path = http_get_path(uri);
+			struct ist newquery = ist2(replace->area, replace->size);
+
+			if (!isttest(path))
+				goto leave;
+
+			err = uri_normalizer_query_sort(istfind(path, '?'), '&', &newquery);
+
+			if (err != URI_NORMALIZER_ERR_NONE)
+				break;
+
+			if (!http_replace_req_query(htx, newquery))
+				goto fail_rewrite;
+
+			break;
+		}
 	}
 
 	switch (err) {
@@ -330,6 +347,11 @@
 			return ACT_RET_PRS_ERR;
 		}
 	}
+	else if (strcmp(args[cur_arg], "sort-query") == 0) {
+		cur_arg++;
+
+		rule->action = ACT_NORMALIZE_URI_SORT_QUERY;
+	}
 	else {
 		memprintf(err, "unknown normalizer '%s'", args[cur_arg]);
 		return ACT_RET_PRS_ERR;