Add support for the Sentiment Check widget

I think the Sentiment check twig template should be vanilla, not opinionated.

i.e.

<div id=”testPlaceholder”></div>
<script type="text/javascript">
    window.onload = function(){
        quickFeed.init({
            placeholder:"testPlaceholder",
            label:"Do you like the website?",
            environment:'uat'.
sourceApplication: 'Your Project Name'
        });   
    };
</script>

This way customisations can be done in a separate module/theme. Also the 'placeHolder' value is optional and when it's not passed, the widget is floated right on the page.

This might be the desired approach for some agencies.

Also the Description field is not used anywhere in the JS snippet (above) so I feel this should be implemented elsewhere in a theme/separate module. CSS overrides would also live in the same place so the module is more generic.

I also wonder if we need consistent names for the blocks? I was searching for 'feedback' initially when placing the block which didn't bring up the One Gov block which might be confusing for others.

Suggested names for the blocks:

NSW feedback (Feedback assist)
NSW feedback (Sentiment check)

Will move the items identified in the comment above ^ to separate issues.