Feature suggestion: add `use_ones` option for 1x numbers

[wdscxsj]

Could you add a use_ones option for 1x numbers, or adjust the current behavior a little bit? That is:

num2cn(16)  # '一十六' (current behavior)
num2cn(16, use_ones=False)   # '十六' (proposed change: feels more natural)
num2cn(116, use_ones=False)  # '一百一十六' (regardless of the value of use_ones)

Thanks!

[zeicold]

I will try to remember what I have done and implement it after that.

[zeicold]

fixed in the coming release