Display search term in box on services page

On page load, display the contents of the filter query parameter
in the search box on the services page.

This requires sanitising the input before displaying it because
sometimes there are naughty people on the internet.
Fix typo in FilteredListView
Make filtered list view take an object of filters

You might want to filter on more than one aspect, eg service name
and which department it belongs to.
Refactor dashboard collection for multiple filters

We want to filter the dashboard collection on multiple facets like
title and department.

To make this easier, use Underscore's filter method to return true
or false based on whether we want the dashboard included in the list.
Write out agencies and departments config files
Add department filtering to services page

This commit adds a select box to the services page to filter
services based on their department.

It generates an array of departments using a dashboard collection
which it uses to populate the select box. We create slugs based on
the department's abbreviation.

This works in browsers with and without JavaScript by adding a
submit button to the form.
Pluralise 'service(s)' correctly on services page
Add agency filtering to services page

This is broadly similar to the departmental filtering.
Show current filter in text title on services page

When the user has filtered the list of services, update the text
underneath the count of services to show what they're currently
filtering as.
Style select boxes on services page