logilab-common #24450 optik_ext import breaks optparse [resolved]

after optik_ext is imported, some stuff is overridden in the optparse module and this breaks help generation of "normal" optparse scripts:

 File "/usr/lib/python2.5/optparse.py", line 1617, in format_option_help
   result.append(OptionContainer.format_option_help(self, formatter))
 File "/home/alf/cubicweb/logilab/common/optik_ext.py", line 277, in format_option_help
   if option.level <= outputlevel and not option.help is SUPPRESS_HELP:
AttributeError: Option instance has no attribute 'level'
appeared in<not specified>
done in0.50.2
load left0.000
closed by<not specified>