Kobo firmware updated to 3.0.0

Kobo have updated firmware to 3.0.0.  No changes needed for the driver
except the version number. Fixes #1251099 [Update to support Kobo firmware 3.0.0](https://bugs.launchpad.net/calibre/+bug/1251099)
DOCX Input: Nicer markup for paragraphs containing only a page break

DOCX Input: Fix page-breaks created as a page break inside an otherwise
empty paragraph not being rendered on conversion to PDF. Fixes #1249502 [Can't apply page breaks on word to pdf](https://bugs.launchpad.net/calibre/+bug/1249502)