(dlg_widget_active): rename to widget_is_active()

...and move to lib/widget/widget-common.c.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
(dlg_replace_widget): rename to widget_replace()

...and move to lib/widget/widget-common.c.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
(dlg_overlap): rename to widget_overlapped()

...and move to lib/widget/widget-common.c.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
Rename functions:

init_widget -> widget_init
create_dlg -> dlg_create
init_dlg -> dlg_init
run_dlg -> dlg_run
destroy_dlg -> dlg_destroy

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
(dlg_default_repaint): make static. Use dlg_default_callback (MSG_DRAW) instead.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>