Make it easier to set page title with a common suffix

[frankieroberto]

Currently we have this in the default layout file:

 <title>{% block pageTitle %}NHS prototype kit{% endblock %}</title>

This makes it possible to override the <title> tag on pages by setting the pageTitle block, but does not make it easy to follow the best practice of having a common suffix for the site name, for example "Achalasia – NHS".

We could improve this by changing the layout to something like:

 <title>{% block pageTitle %}{% if pageName %}{{ pageName }} - {% endif %}}{{ serviceName }}{% endblock %}</title>

Which would then allow you to set a pageName attribute on pages and have your serviceName as a suffix.

You could still override the whole thing by using the existing pageTitle block.