Usage: <tt> input = <i>vratio</i>  multiplyvelocity</tt>

<p>
The velocity <tt>VSR</tt> of all atoms is multiplied by <tt><i>vratio</i></tt>.
If a thermostat is used, the velocity of the thermostat variable (<tt>zetav</tt>)
 is multiplied by <tt>vratio</tt> as well.  If a barostat is used, the velocity 
of the box matrix <tt>VH</tt> is also multiplied by <tt>vratio</tt>.

<p>
Also see <tt>scaleVel</tt>.
