sqlline does not allow for a password prompt - security issue

When authentication is enabled in drill, and using sqlline, there is no way to get the sqlline client to prompt for a password. The only option is to specify the password at the command line (-n user -p password) or to log in and then connect.

This is a security risk, in that now the .bash_history contains the user's password, defeating accountability on the system. Hive and MYSQL both allow for a -p flag with no value to trigger a prompt for the password that is not logged by .bash_history.

One work around is to connect after starting sqlline, however, if the sqlline command offers a way to specify the username/password, we should do it in a way that doesn't violate security principles.