prettify-status.pl: use a hashref for data rows

This lets us save much more information about each row, which will
be important later for making decisions about how to render it.
prettify-status.pl: use text block for HTML header
prettify-status.pl: leave tag empty if no version
prettify-status.pl: split tag link to variable

And if there is no tag, do not use a link at all.
prettify-status.pl: parse empty versions too

If the version is left blank, we can still handle that, rather than
resorting to showing the line as a warning.

This eliminates the ugly warnings of the form:
* "foo:bar: 0 commits on master since "
prettify-status.pl: separate out empty versions

If the latest version is unknown/blank, log the entry into its
own table, rather than mixing it in to the "Released" table.
prettify-status.pl: use groupId as org if unknown
prettify-status.pl: reorganize header generation

Rather than hacking the data structures, let's handle
header output during the page generation phase.
prettify-status.pl: add a toggle for each project

This can help filter out the noise. Hooray for jQuery!
prettify-status.pl: put released table first

Otherwise, it is difficult to style the unknown table as floating
on the right-hand side, and have the layout work as desired.
prettify-status.pl: fix sorting of lines