Adds option to separate function of "URL" into (listed) "URL" and "Target URL" to allow for more flexibility (in that case if target URL is empty, bibliography mark hyperlink leads to bibliography table row if possible)
When writing tests also found and fixed bug where exporting new file with anchor link bibliography mark crashes LO.
Change-Id: Ic1b5c8c9590c0338dcfc4fa3a981142bddae0113
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/147868
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>