[bfss] fix file update to ensure file's content is available on the fs asap...
and not only at commit time. So it's consistent with entity creation behaviour.
The new file is created at assignement time and removed if the commit is
rollbacked.
# -*- shell-script -*-
###############################################################################
#
# put here information about external resources used by your components,
# or to overides existing external resources configuration
#
###############################################################################
# CSS stylesheets to include in HTML headers
# uncomment the line below to use template specific stylesheet
# STYLESHEETS = DATADIR/cubes.%(cubename)s.css