Move error reporting code to a separate function 'PMA_Error_Handler::reportError()'. Hook it in 'PMA_Footer::getErrorMessages()'.

Signed-off-by: Dhananjay Nakrani <dhananjaynakrani@gmail.com>
Remove included 'common_error_reporting.php' script and its inclusion from all the scripts.

Signed-off-by: Dhananjay Nakrani <dhananjaynakrani@gmail.com>