Mostly generated with a script from Wikipedia data (only the typical
positive ratio is slightly modified).
This is a first test before adding my generating script to the main tree.
Some charsets are simply not supported (ex: fr:iso-8859-1), some are
temporarily deactivated (ex: hu:iso-8859-2) and some are wrongly
detected as closely related charsets.
These were broken (or not efficient) from the start, and there is no
need to pollute the `make test` output with these, which may make us
miss when actual regressions will occur. So let's hide these away for
now until we can improve the situation.