Support notebook internal link

[alxnbl]

Replace inside notes link to url starting by onenote:// by a markdown reference.
If the link point to a page outside of the notebook, keep it unmodified.

[meichthys]

This would be a huge improvement. Would be helpful if this was also added to the markdown export type as well.

[Argimko]

This should be labeled as good-start-to-being-a-hero )))