Allow transversal in RegExpVisitor

[connor4312]

Estraverse allows the visitor to do several things in its functions:

• return skip to avoid recursion
• return break to stop iteration
• call a replace function to replace the current node

It would be useful to implement these in regexpp as well.

[MichaelDeBoey]

Hi @connor4312!

Since this repo is unmaintained, you might want to re-open this issue in the @eslint-community fork https://github.com/eslint-community/regexpp

For more info about why we created this organization, you can read https://eslint.org/blog/2023/03/announcing-eslint-community-org