p_purge_metadata now updates the metadata cache and the INFO array like the other metadata writing functions

The media options dialog has currently an open bug regarding the
behavior of the nolink option. Additionally will wrong syntax be
inserted when using Internet Explorer < 8. Since this can't be
fixed on time, this patch disables the media options for the release.

The redirect target URL is constructed with escaped ampersands since b6258081.
Thanks to Chris Tapp for pointing out.

I used the Latin of the first century
B.C., so the word are written as Cicero wrote: for example there isn't
the 'v' letter unless in capital form and if the word ending in -uus
or -uum, I wrote -uos and -uom. This form of Latin, as I said, is that
of the classic authores as Cicero, Caesar, Sallustius etc...