* "`currentlang()`" - tests whether a page is written in the same
language as the current page.
* "`needstranslation()`" - tests whether a page needs translation
- work. Only slave pages match this PageSpec.
+ work. Only slave pages match this PageSpec. A minimum target
+ translation percentage can optionally be passed as an integer
+ parameter: "`needstranslation(50)`" matches only pages less than 50%
+ translated.
Note that every non-po page is considered to be written in
`po_master_language`, as specified in `ikiwiki.setup`.