Fix continuous integration tests for PHP 5.3.
Fix continuous integration tests for PHP 5.3.

Error message:
    Parse error: syntax error, unexpected T_CLASS, expecting T_STRING or T_VARIABLE or '$' in [...]

php-curl-class/php-curl-class,zachborboa/php-curl-class,zachborboa/php-curl-class,zachborboa/php-curl-class,php-curl-class/php-curl-class,php-curl-class/php-curl-class