Issue #129 (MySqlStreamer fails on warning with mysql version 5.6.10)

This changes `MySqlStreamer` to pass a temporary option file to the `mysql` binary.  This addresses the potential security vulnerability caused by passing the password on the command line.  Newer versions of `mysql` (at least one) generate a warning in this case.

The behavior *should* be equivalent to the previous version, but will run on versions of `mysql` that generate the warning.