Change lowercasing table link to quoting

We can't reliably lowercase the title of our graphs, as it results in bugs
like 'Table view of stages of making an lpa data' and 'Table view of how people
access gov.uk data'.

Instead, use quotes like 'Table view of "Stages of making an LPA" data' and
'Table view of "How people access GOV.UK" data'
Remove NTA tabular numbers from header

NTA tabular numbers causes an issue in Chrome on Windows that we
first encountered in 358e541c5e4d1ab873fa0bd3d7ea8dd1aa76549b

https://code.google.com/p/chromium/issues/detail?id=344347

This is particularly visible in the page header. We should never
need to display fixed width numbers in the header anyway.

Thanks to @ianhopkinson for the bug report.
Merge pull request #303 from alphagov/bugfix-lowercase-links-and-underlines

Bugfixes: lowercase links and header underlines