* applied gimp-lecorfec-99041[02]-0, changes follow

* plug-ins/FractalExplorer/Dialogs.h (make_color_map):
replaced free with g_free to fix segfault.

* plug-ins/Lighting/lighting_preview.c (compute_preview):
allocate xpostab and ypostab only when needed (it could also be
allocated on stack with a compilation-fixed size like MapObject).
It avoids to lose some Kb on each preview :)
Also reindented (unfortunate C-c C-q) some other lines.

* plug-ins/Lighting/lighting_main.c (run):
release allocated postabs.

* plug-ins/Lighting/lighting_ui.c:
callbacks now have only one argument because gck widget use
gtk_signal_connect_object. Caused segfault for scale widget.

* plug-ins/autocrop/autocrop.c (doit):
return if image has only background (thus fixing a segfault).

* plug-ins/emboss/emboss.c (pluginCore, emboss_do_preview):
replaced malloc/free with g_malloc/g_free (unneeded, but
shouldn't everyone use glib calls ? :)

* plug-ins/flame/flame.c :
replaced a seg...