make-json --domain flag

[drzraf]

Feature Request

• Yes, I reviewed the contribution guidelines.

Describe your use case and the problem you are facing

I'm retrieving my PO files from a translation platform (Weblate using wlc).
Said files are missing a proper Domain header and still, I'd expect make-json to be able to deal with that and output correctly named files.

Control over filename is important enough to not just be derived from the header but being given explicit value at the make-json step.

Describe the solution you'd like

A --domain flag taking over the autodetection of PO file hedader.

Workaround

$ rename -v -f -d -e "s/^(?!$(I18N_DOMAIN))/$(I18N_DOMAIN)-/" *json

References

See also #313 and #197 (comment)