Splits a converted document back into its pages on the <!-- Page N --> markers.
The inverse of buildMarkdown, and the reason the markers are machine
readable at all: re-running the pages that failed means finding them, converting
them, and splicing them back.
Splits a converted document back into its pages on the
<!-- Page N -->markers.The inverse of buildMarkdown, and the reason the markers are machine readable at all: re-running the pages that failed means finding them, converting them, and splicing them back.