Merge pull request #367 from alphagov/feature/view-driving-record-digital-transactions

Added config for the digital transactions module (grouped timeseries).
Add Solihull dashboard to prototypes page

Resize 'Staff in government buildings' screenshot so that it's the
correct size for the space it now occupies.

Remove unused Sass.
Merge pull request #368 from alphagov/69256122-add-solihull-prototypes

Add Solihull dashboard to prototypes page
Add realtime/availability modules for "view your driving record"
Merge pull request #370 from alphagov/feature/viewing-driving-record-realtime-and-uptime

Add realtime/availability modules for "view your driving record"
Added config for driving record login module
Make Collection#fraction return null for undefined values

Need to make sure graphs display a no data message instead of a value of NaN