Ability use args, kwargs with delimiter

[nborisenko]

Fire now try to parse flat args and kwargs, but often this not convenient
Example:

import fire


def test(*args, **kwargs):
    print(kwargs)
    print(args)


fire.Fire(test)

python main.py arg1 arg2 --kwarg1 1 --kwarg2 2

{'kwarg1': 1, 'kwarg2': 2} ('arg1', 'arg2')

In some cases will be much more simple have opportunity to set *args **kwargs like this :
python main.py --args arg1 --args arg2 --kwargs kwarg1=1 --kwargs kwarg2=2

[ljluestc]

import fire

def test(*args, **kwargs):
print(kwargs)
print(args)

class ArgsAndKwargs:
def init(self):
self.args = []
self.kwargs = {}

def add_args(self, *args):
    self.args.extend(args)

def add_kwargs(self, **kwargs):
    self.kwargs.update(kwargs)

def main(**params):
args_and_kwargs = ArgsAndKwargs()

if 'args' in params:
    args_and_kwargs.add_args(*params['args'])
if 'kwargs' in params:
    args_and_kwargs.add_kwargs(**params['kwargs'])

test(*args_and_kwargs.args, **args_and_kwargs.kwargs)

fire.Fire(main)