Log cold candidate eligibility and reservation changes

tests/test_nat_detection.c

@@ -111,6 +111,7 @@ static void test_all_groups_tcp(void) {
 
 int main(void) {
     debug_config_init(); debug_set_level(DEBUG_LEVEL_WARN); debug_set_category_level(DEBUG_CATEGORY_NAT, DEBUG_LEVEL_DEBUG);
+    if (getenv("UTUN_TEST_DEBUG")) debug_set_category_level(DEBUG_CATEGORY_BGP, DEBUG_LEVEL_DEBUG);
     struct nat_fixture fixture; nat_fixture_init(&fixture);
     struct SC_MYKEYS first, second;
     assert(sc_generate_keypair(&first) == SC_OK && sc_generate_keypair(&second) == SC_OK);