After the server PHP upgrade I am getting the following error with PHP Version 5.6.2 on Apache 2.0

Question:
After the server PHP upgrade I am getting the following error with PHP Version 5.6.2 on Apache 2.0

A PHP Error was encountered
Severity: Notice
Message: Only variable references should be returned by reference
Filename: core/Common.php
Line Number: 257

Solution:

Edit filename: core/Common.php, line number: 257

Before

return $_config[0] =& $config; 
After

$_config[0] =& $config;
return $_config[0];