Add patient size data config option

[Ed McDonagh]

Refs #140

Add a configuration option for display of patient size information on summary filter pages.

When there is no size information in the database, it wastes space. But when there is it is really useful. Therefore add if statements to templates and pass the value of the config item from the database via the view.

[Ed McDonagh]

Marking as won't-fix as we're unlikely to do this now.