Add a recommendation about signatures

[nathanmsmith]

In my experience, I've found that using flexbox or similarly responsive design tools allow for accurate handling of longer signatures.

In cases where signature input is fixed, omitting middle names is an acceptable option. What's tricky is determining what a first and last name are. A naive approach would be to split a name on spaces and then take the first and last elements of the resulting array. But this doesn't handle last names like de la Cruz where the last name is made up of multiple parts all separated by spaces. I don't have a great solution, would love to discuss more.

Initial only signatures can also be used in places. As @juliemeridian notes a good default may be single initial firstname + multiple initial last name.

[juliemeridian]

I got back around to updating ProperName and added a short section about initials that links back to this issue about ways to handle signatures. Thanks for the input!