Added print_bin() method

[R3tr0BoiDX]

I added a method, that prints outs all the bins. May need an additional option to make this optional.

[benmaier]

Hi, thanks for the contribution! I don't have time to check this properly atm, but the following things need to be done before merging is possible

1. please do not use format strings (f"{}"), they were introduced in Python 3.6 and will break backwards-compatibility
2. add a boolean keyword argument to the respective functions that switches printing bins on and off, please have it off as default (because people use this on large data sets, which will make the CLI unusable)
3. add a similar boolean option to the CLI procedure

[R3tr0BoiDX]

Okay, I added the -p option. I never worked with the OptionParser. I hope I did that in the right manner.