Enable PHP error reporting when in dev deployment

[rht]

See https://www.mediawiki.org/wiki/Manual:How_to_debug

To see PHP errors, add this to the second line from the top (right below the <?php) of LocalSettings.php:
error_reporting( -1 );
ini_set( 'display_errors', 1 );

Or set it in php.ini:
error_reporting = E_ALL
display_errors = On

Or set in .htaccess:
php_value error_reporting -1
php_flag display_errors On