You can now override default table sorting

index.php now checks for a query parameter called "sort" and will
use this instead of the default order.
turn overview line chart dots into links

When you click on a data point in an overview line chart,
it now takes you to the build results for that day sorted by
the relevant measurement.
Fix potential off-by-one error on line chart dates

Picking a moment in time in the middle of the daily time range
is much safer than relying on the beginning or end to actually
fall on the date in question.
Make overview links jump to the correct section

When you click on a data point in an overview line chart, it will
now link you directly to the appropriate build group on index.php.
Merge remote-tracking branch 'origin/master' into overview_links
Better handling for charts with only one value.
Add page generation time to overview
open link in new tab instead
Merge pull request #8 from Kitware/overview_links

Create links from overview.php