Expand on which templates engines we support

[chrisdel101]

Description

A #1588 (comment) made previously:

It refers to the template engines page, the last part of this sentence.

The Express application generator uses Pug as its default, but it also supports Handlebars, and EJS, among others.

Which others?

Suggest literally adding a list for better support. May require input from @expressjs/express-tc to answer this.

Expectations

Adding list of all templates supported, or at least a variety on top of the big four. Else, remove the wording "among others."

[wesleytodd]

I think the medium to long term goal is to remove the template engines from "core" express and move things over to middleware (details TBD I think). I don't know if that should change the plans for documentation, but just wanted to call it out since I saw this issue.