Don't echo password to console when asking for mysql root password

[reedy]

Warning: mysql_connect(): Access denied for user 'mw_bench'@'localhost' (using password: YES) in /home/reedy/oss-performance/base/DatabaseInstaller.php on line 50

Warning: mysql_select_db() expects parameter 2 to be resource, boolean given in /home/reedy/oss-performance/base/DatabaseInstaller.php on line 51
Can't connect to database (mysql -h 127.0.0.1 -pmw_bench -u mw_bench mw_bench). This can be fixed for you.
MySQL admin user (default is 'root'): 
MySQL admin password: password_in_clear_text