pdLastUsedSettings: add support for the button strip UC

Most dialogs use the command bar UC to save/load last-used settings.

The main window toolbox doesn't have this luxury, so it leans on a
separate pdLastUsedSettings class.  That class had not been updated to
save values for the new button strip UC.
Lasso selections: disallow "border type" selections

Border-type lasso selections can still be created using the Select menu,
once the lasso is complete.  The math for creating them dynamically at
draw-time is hideously complex and not worth the trouble, so I prefer to
just hide the option entirely.