Len'en Project support

[mokou]

[nmlgc]

Len'en translations are currently being developed by @yoshiquest using an overlay-based solution. I haven't seen any user comments about this system, so I don't know if that's already enough for people or if they indeed want full moddability with thcrap.

That said, if we did want to patch this series and it turns out to be viable with thcrap's model, we should have #38 first. Len'en is a less established series with no static patches out there as far as I'm aware, so none of the arguments against using dictionary-based translations apply to it.