Allow input formats for date

Input files can contain dates (and datetime) as strings in different formats. Power BI seems to have some rules to recognise these, but surely these rules will prove to be region dependent.
Typical cases are:
- dd/mm/yyyy but also mm/dd/yyyy . Currently Power BI does a guess, but then does not warn when it finds illegal dates (month between 13 and 31).
- yyyymmdd and all dates with 2 digits for the year will be problematic.
- unusal separators
The correct solution would be that we can specify an input date format, at least per input source and perhaps also per column. (Yes, the same problem exists in Excel)...