Improved the documentation for Zen::Language.
Improved the documentation for Zen::Language.

This should hopefully clear up potential problems with loading language files
and using translations.

Signed-off-by: Yorick Peterse <266d235124591138fa7ddf38558bc72e4619a5da@isset.nl>

YorickPeterse/zen-cms,YorickPeterse/zen-cms