Add null to possible types for wrapper. (#380)
Add null to possible types for wrapper. (#380)

This is already described in documentation, so does not require any
further changes.

Co-authored-by: mjfwebb <17b9e1c64588c7fa6419b4d29dc1f4426279ba01@w3bb.net>
yaycmyk/markdown-to-jsx,probablyup/markdown-to-jsx,probablyup/markdown-to-jsx,yaycmyk/markdown-to-jsx