Translation of Filter of Date Columns

[RogerPenna]

I noticed the Date Filter is shown only in English

Paul-Grist said the following on the topic in the forum

Hmm someone needs to go into this code: https://github.com/gristlabs/grist-core/blob/d008a32eb3eef6fb7d233b8a0d85fced3209abcd/app/client/ui/DateRangeOptions.ts#L9-L41

and mark the text there in the special way that makes it translatable. It is a small and hopefully easy piece of work..