Initial commit of new MSWord-to-ODF filter.
I didn't enable it in cmake yet - just add the msword-odf directory in the same place as the other msword directory in CMakeLists.txt if you want to use it.

This code should compile and produce an ODT with the text from the .doc, but it's not formatted at all.
That's next on the list.

There's also a lot of commented-out code from the other filter, which can eventually be removed.