core/config: Fix _regid/regid confusion.

Closes #22.

gocollect.conf.sample

@@ -13,9 +13,9 @@ register_url = http://localhost:8000/register/
 
 # push_url: Specify URL where to post the data.
 #   The {ip4} and {fqdn} parameters are taken from the core.id script.
+#   The {regid} parameter is the (unique) identifier obtained from
+#   the registry; also taken from the core.id script.
 #   The {_collector} parameter is the collector name/key.
-#   The {_regid} parameter is the (unique) identifier obtained from
-#   the registry.
 #
 #   For now, we've decided to do without auth on the collector server.
 #   We won't do automatic billing based on the imported values and the

gocollector/actions.go

@@ -136,8 +136,7 @@ func register(registerURL string, coreIDData Collected,
 	}
 
 	os.MkdirAll(path.Dir(regidFilename), 0755)
-	err = ioutil.WriteFile(
-		"/var/lib/gocollect/core.id.regid", []byte(value), 0400)
+	err = ioutil.WriteFile(regidFilename, []byte(value), 0400)
 	if err != nil {
 		logger.Fatal("Could not write core.id.regid: ", err)
 		return false