Update the display when showing debug info

Make the list an ordered-list as it has order. Then add a start which
matches the start offset which has been requested.

Also put the debug info back onto one line as it makes it easier to work
with.
Merge pull request #661 from alphagov/debug-updates

Update the display when showing debug info
Change jump-links to popular links

We are seeing people browsing then searching for common user needs. Try
and get those people the result they want before they try and find it
from browse.
Merge pull request #663 from alphagov/homepage-links

Change jump-links to popular links