Add m-0-auto class to achieve margin: 0 auto;

[carlosmori]

Hey guys,
do you think is a good idea to add a class like m-0-auto to achieve margin: 0 auto.

If you think is a good idea I would like to make a PR it would be my first collab!

Thanks and amazing library!

[trm217]

You can achieve this by just using .mx-auto

[carlosmori]

Got it, thanks!