Changes to all the opening and saving file dialogs.
This corresponds to one component of the patch_II file attached to https://gna.org/task/?6847 by Michael Bieri (https://gna.org/users/michaelbieri).
The following have been changed: filesavebox() -> savefile(), fileopenbox() -> openfile(), fileopenbox() -> multi_openfile(),
Authored by: bugman 2010-01-14
Parent: [r10216]
Child: [r10218]
