Date blurring in free text

[RudolfCardinal]

Request for generic date blurring in free text -- an extension of scrub_all_dates.

User interface could be:

• date_replacement_text -- defaults to replace_nonspecific_info_with, but could also be something like [%Y-%m] (with substitution codes based on a very small subset of https://docs.python.org/3/library/datetime.html#strftime-strptime-behavior), allowing user-defined boundary marking

Implementation would likely need:

• extension of current get_generic_date_regex_elements() function to add named groups, or similar, if required;
• a function to generate a date from string components from those named capture groups, e.g. date_from_string_components(year="02", month="Sep", date="3") -> datetime.date(2002, 9, 3);
• a reasonably efficient way to iterate through a string and perform these replacements;
• if date_replacement_text (having been safety-validated) is non-empty, then separate dates out from the "generic" massive regex, and run the separate process (which will be slower)

[RudolfCardinal]

And because Python is brilliant, the third step is handled by the form of re.sub in which repl is a function (https://docs.python.org/3/library/re.html#re.sub).