Specify which elements are to be expected in which order for incomplete dates

In my work I am facing dates that can have different shapes. The dates are meant to specify a certain period, which can be more or less specific. The date always contains a year. After that it might contain a month. If we're really lucky, it also contains a day.

Some examples:

• 28 (which means ??/??/2028)
• 11/28 (which means ??/11/2028)
• November-2028 (which means ??/11/2028)
• 2028 (which means ??/??/2028)
• 15/11/28 (which means 15/11/2028)

I guess you get it.

Hours and minutes are not relevant to me, but I guess it could be implemented in the same pull request.

I expect a setting to be shaped as follows:
settings={'ELEMENT_EXPECTATION_ORDER':'YMDhms'}

(not sure about the hour, minute, second signage)

The parser will follow this order to find the elements. Thus beginning with the year,
If the parser encounters an element that is possibly a month or a year, it will check the order and choose to name it was a year accordingly. Then it will proceed with the next in line.

No file, test, or entry point is named in the issue. Start by locating the date parser and settings handling, then determine how incomplete dates and ambiguous numeric elements are currently processed. Done means the requested element-order setting and the listed year/month/day examples have defined, tested behavior, including the unresolved time-element notation.