Changed the header for the script and provided more info for Error cases

Would rem be better? If done after the echo off call, it won't show up on a command window.

> On Sep 19, 2014, at 1:15 PM, "Lou Amadio" <notifications@github.com> wrote:
> 
> In scripts/apply-BootMedia.cmd:
> 
> >  @echo off
> > +echo **************************************************************************
> This shouldn't be echo'd
> 
> —
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