Add custom options to input tags

[dwasyl]

When styling form inputs, it is not possible to add any extra options (beyond data-* properties). Could an option be created to add additional options to the input? In this cases I'm thinking of the size property, but there are likely other options people may find useful.

[vedmack]

I won't be able to add it in the near future, but since its something that can be easily added in PR, feel free to do so