docs(ngBindHtml): Added important info to comment

Added comment. It doesn't say you need to include angular-sanitize.js otherwise ngSanitize will cause an error!
Well it would have helped me to make it run. There was no info about the
file, how should one know? I found out on stackoverflow and was pissed off
enough to make that change. So please let others know, what is a comment
then for?
Am 02.10.2014 22:15 schrieb "Caitlin Potter" <notifications@github.com>:

> In src/ng/directive/ngBind.js:
>
> > @@ -145,7 +145,8 @@ var ngBindTemplateDirective = ['$interpolate', '$compile', function($interpolate
> >   * element in a secure way.  By default, the innerHTML-ed content will be sanitized using the {@link
> >   * ngSanitize.$sanitize $sanitize} service.  To utilize this functionality, ensure that `$sanitize`
> >   * is available, for example, by including {@link ngSanitize} in your module's dependencies (not in
> > - * core Angular.)  You may also bypass sanitization for values you know are safe. To do so, bind to
> > + * core Angular). In order to use {@link ngSanitize} in your module's dependencies, you need to add "angular-sanitize.js" to your index.html.
> > + * You may also bypass sanitization for values you know are safe. To do so, bind to
>
> I don't think this change is adding much --- the specific instructions are
> only helpful to people under a specific configuration, and the real
> instructions for this are laid out more clearly in the tutorial
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/angular/angular.js/pull/9400/files#r18364209>.
>