Provide previous versions of fuzzy strings

[afranke]

msgmerge has a --previous option that keeps the previous version of a string as a comment when it creates a fuzzy one. It is extremely useful in determining why a given string turned into a fuzzy and what changes need to be applied to the translation, if any.

Could you please add that to the fields of a message?

[afranke]

For reference, here’s an example of what it looks like:

#: data/org.gnome.Fractal.gschema.xml.in:23
#, fuzzy
#| msgid "Sessions"
msgid "Session settings"
msgstr "Sessions"

[afranke]

In the PO file format description, it’s called previous-untranslated-string. While I didn’t think of it initially, it would make sense to also provide previous-context.