Added improve dashboard message to the footer.

Config driven for high transaction services.
Rejigged the footer layout.

We now have (3 + (3 + 3)) layout on the footer.

Fixed CSS styles as per image in story.
Links should be blue.

The underline might be enough in other circumstances, but here it looks like we're just underlining the heading.

I was prompted today - Matt mentioned that Lindsey from Student Finance
hadn't noticed the module pages existed at all. I think this will go some
way to fixing that problem, and is better than adding a 'more details' link
to every module.

Next, blue clashes hard with the blue-green, so we also lose the blue-green.
Merge pull request #353 from alphagov/links-should-be-blue

Links should be blue
Allow configurable weekly periods for KPIs.

Most KPIs are monthly, but the waste carriers dashboard supplies
cost data weekly.

Extend the KPI module to handle this nicely.

Update tests.
Add cost per transaction to waste carriers dashboard
Fix bug in positioning of line labels.

On line graphs where the top label is very near the top of
the graph, label positioning was odd.

This was because an extra margin of 40px was being applied,
even though this margin was only used for stacked graphs
with a summary legend in the top right corner.

Line graphs do not require the summary legend, so remove the
extra margin.

The best place to see the difference is the G-Cloud dashboard.
Merge pull request #354 from alphagov/feature/cost-per-transaction-waste-carriers

Cost per transaction on waste carriers
Merge pull request #355 from alphagov/bugfix/position-of-line-graph-labels

Fix bug in positioning of line labels.
Ensure KPIs fail gracefully for empty datasets.

If there is no data in a dataset, ensure the KPI modules
do not crash and burn. Also update tests.
Merge pull request #356 from alphagov/bugfix/crashing-bug-in-kpi-module

Ensure KPIs fail gracefully for empty datasets.
Change format of email link
Merge pull request #352 from alphagov/feature/footerUpdates

Feature/footer updates
Discard any data over 24 hours old in realtime view.

Some of our realtime views show 25 or 26 hours' worth
of data. This is because our realtime collections inherit
from the list collection, and so we return the latest N
data points, with no control over how old these are. If
the realtime collectors have been down at any point in the
last 24 hours, the data returned can go back further in
time.

So: add a small fix in the realtime view to discard any
data that is more than 24 hours older than the most
recent data point. This will stop the confusing messages
about there being 25 hours' worth of data.

We have a story for a proper fix, which is to convert
the realtime collections to use timestamps, rather than
inherit from the list collection. However, this fix will
work in the short term.
Merge pull request #357 from alphagov/bugfix/show-24-hours-data-on-realtime

Discard any data over 24 hours old in realtime view.
Implemented KPI modules on carers allowance dashboard
Implemented KPI modules on SORN dashboard
Converted exisiting KPI modules to use sigfigs instead of dps
Use pence option for currency formatting in cost-per-transaction modules

dps options will not add trailing zero to multiples of 0.1
Added KPIs to deposit foreign marriage dashboard