Support eurodate format (dd-mmm-yy with a digit month)

We have support for dates of the form `dd-mmm-yy` where `mmm` is an alphanumeric literal; for example:
```
"15-Jan-2017"
```

However, there is a European date format that is similar where `mmm` is a digit; for example:
```
"15-01-2017"
```

The above fails to parse with:
```
Could not find format for "28-02-02"
```