Add additional date formats

[nf9k]

From runtime output: Please use either YYYY-MM-DD, YYYY-MM, or YYYY format.

I'm from the US and was trying to use MM-DD-YYYY.

Perhaps consider allowing two digit years? It'll be a while before Y3k.

[sinaatalay]

Thank you for opening an issue. I don't think we need to add new date formats because the dates in the YAML file are meant to be pure date data in ISO 8601 format. They are not printed in PDF in that format anyway. They are converted into normal English strings (or into any language, by updating locale_catalog field in the YAML file).

Allowing two digits would be a problem because people still use the 1980s and 1990s in their CVs.

[nf9k]

Again, something else I discovered after rendering and playing around a bit.

Thank you, again!