avoid errors when error_reporting(E_ALL) is enabled
avoid errors when error_reporting(E_ALL) is enabled

StefanStas/mavenlink_php_api,StefanStas/mavenlink_php_api,derekshull/mavenlink_php_api,mavenlink/mavenlink_php_api,derekshull/mavenlink_php_api,mavenlink/mavenlink_php_api