setup: make 'clean' command compatible again with distutils
After the switch of 'my_clean' to a simple Command, the 'clean' command
has no more bits for options, resulting in distutils (either external
or embedded in setuptools) complaining about it:
distutils.errors.DistutilsClassError: command class <class '__main__.my_clean'> must provide 'user_options' attribute (a list of tuples)
To overcome that, provide all the standard bits from options, i.e. the
'user_options' list, and the 'initialize_options' & 'finalize_options'
methods. In addition, add a dummy 'all' option, as distutils wants it:
error: error in [...]/.pydistutils.cfg: command 'my_clean' has no such option 'all'
Fixes commit
a965c91c6fa1275613edbbef75c0422574eb9ff2
Signed-off-by: Pino Toscano <[email protected]>