fix warnings appearing with -Wextra

This fixes pretty much exclusively unsued-parameter
warnings. Removes some function parameters which have
fallen out of use and also the permutating parameter
test. The latter did not really do what it promised
and was pretty much beyond repair.

tests/test-output-pgsql.cpp

@@ -264,6 +264,8 @@ void test_clone() {
 } // anonymous namespace
 
 int main(int argc, char *argv[]) {
+    (void)argc;
+    (void)argv;
     // remove flat nodes file  on exit - it's 20GB and bad manners to
     // leave that lying around on the filesystem.
     cleanup::file flat_nodes_file(FLAT_NODES_FILE_NAME);