If TextBox contained text that is larger than the box, and
autofit was off, and autosize was off, and full width was off,
then text always aligned to box's left top corner, regardless of
text anchor setting.

Related problem (i103454) was fixed in 2009 by Armin Le Grand, but
only for full width text. This patch extends the scope of that fix
to correctly process other cases.

The fix introduces a new compatibility flag:
AnchoredTextOverflowLegacy
If it is true, then old behaviour is retained.
It is always false for new documents and imported documents.
When opening existing ODF documents, it's true by default, unless
it is explicitly set in settings.xml.

Unfortunately, I couldn't find a way to access the document model
from any of SfxBaseModel::load() or SfxObjectShell::DoLoad, where
it could enable setting the compatibility flag universally when
loading own format. Instead, I had to do it individually in each
of SfxObjectShell::Load() implementations.

Unit test is included.

Change-Id: Ifad79d546739daafff59fb6c7fb0dce51babc53d
Reviewed-on: https://gerrit.libreoffice.org/26737Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>