TMSFNCPanel header features

  1. An option to choose the default orientation of the expander button. The current default is appropriate to a free-standing panel, but when using a panel embedded with a splitter it makes more sense to have them the other way around.

  2. When collapsing the panel with the compact button it would be nice to have the header change orientation and still be visible - the panel currently just shows whitespace when in a compacted state.