Add all bootstrap packages in DefaultBuildProfiles

* Don't handle the bootstrap case in the main Jamfile. Add all bootstrap
  packages to the image in the profile definition. That's less
  confusing, hopefully.
* Add the missing bootstrap packages (ncurses*, libtool_libltdl). The
  would normally be added in build_haiku_image when the package
  dependencies are resolved, but we don't do that for the bootstrap
  image, since we intentionally leave some dependencies out (e.g. perl)
  because they can be built.