- teach comphelper::containerToSequence to handle sized arrays
- also use range based for-loop where appropriate.

Change-Id: I73ba9b6295e7b29c872ee53de7a9340969e07f99
Reviewed-on: https://gerrit.libreoffice.org/38769Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
Tested-by: Noel Grandin <noel.grandin@collabora.co.uk>