Wikimedia subspp

Mostly changes to catch subspecies, varieties, and hybrids, as discussed in EoL curators list.
Just had another look, and I think I've got it right here. The confusion comes because we could have `Varietas|Picea abies var. acuminata` or simply `Varietas|acuminata`. This part of the code only gets used in the second case, for a single-word epithet (this is actually the much rarer case). So if we have a single-word variety, we check if we already have a (fully assembled) subspecies name like `Picea abies subsp. foo`. If so, we simply append the variety (`Picea abies subsp. foo var. acuminata`). If not we check if we have a valid species name instead, like `Picea abies`, and append the single variety word to that instead.

As I said, this is all pretty rare, although I think I check on the construction in the unit tests.