Series import: recognize "грн" as UAH

[php-coder]

m.w.f.s.i.SeriesInfoExtractorServiceImpl : Determine currency from 'грн'
m.w.f.s.i.SeriesInfoExtractorServiceImpl : Could not extract currency from a fragment

This have a higher priority until #1216 is resolved.

[php-coder]

We can workaround it with currency-value.