Make output while tagstats is running easier to read.
Add Key Comparison page.

This allows comparing of two or more (up to five) keys on one page.
No link currently points to this page.
Better display of prevalent values on key comparison page.
Fix bug in turbo_link call.
Add JSON button to all flexigrid tables.

If you click on the button you get the same content the table is currently
showing as JSON.
Remove carriage returns and clean up whitespaces.
Add API link to footer of all pages.
Remove switch to show older API versions because there aren't any.
Add request url to API json output.
Don't show map on key comparison page if there isn't one.