- I had to convert SwFrmFmts, SwSpzFrmFmts, SwCharFmts, SwSectionsFmts,
  SwTextFormatColl, SwGrfFmtColl all together because of the code that wants
  to work with any of them.
- Introduce a pure virtual base class SwFmtsBase, since there are a handful
  of methods that want to work with any of the std::vector<Sw*Fmt> types.
- the class SwSpzFrmFmts was dropped, and the code changed to use SwFrmFmts
  instead, since the 2 types are identical.

Change-Id: I8c4056b5aedd574a33666e2d649a8b849958441c
Signed-off-by: Fridrich Štrba <fridrich.strba@bluewin.ch>