Removal of ClientBuilder::defaultLogger()edit

In 5.x there is the ability to create a default Logger object, which has been removed. It is now required to explicitly make a Logger object.

5.x

$logger = ClientBuilder::defaultLogger('path_to_log_file');

6.5

$logger = new Logger('name');
$logger->pushHandler(new StreamHandler('path_to_log_file', Logger::WARNING);