This solution comes with a few limitations. The bullet isn't centered in
Powerpoint and has to be between 25% and 400% of the size of the first
character in the paragraph. This isn't optimal, but should produce
acceptable results under most circumstances.

Change-Id: I6c37169282aa351b81d78e06678424203b78f6d7
Reviewed-on: https://gerrit.libreoffice.org/44911Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Tamás Zolnai <tamas.zolnai@collabora.com>