Bump compat level to 9
Imported Upstream version 2.3
Merge tag 'upstream/2.3'

Upstream version 2.3
Add dependency on libssl-dev
Add links to manpage for new commands
Update .gitignore
Refresh d/patches

* Remove numbers to avoid renames when a patch is removed.
* 0001-Fix-script-syntax-check.patch merged upstream.
Update changelog