Writer doesn't support foot or endnotes in TextFrames, so they are not
supported in OOXML floattables, either. In the past, floattables were
imported as normal tables, that's how this worked. Restore the old
situation till the core limitation is there, so we at least don't
regress.

Change-Id: I4eb62617e3131176f7371e9ca69f11bc9e948a0b