feat(modal): add modalDialogClass to modal-dialog div

[MisuleT]

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[jnizet]

Hi @MisuleT

Thanks for the PR, but could you please explain why you think we should add such a configuration option? Can't you use the already supported windowClass option?

For example with such a selector in your stylesheet:

.myCustomWindowClass .modal-dialog {
  ...
}

[MisuleT]

Hi @jnizet

We depend on another library in our project, that is based on Bootstrap. We already use windowClass, but we have to add another class to modal-dialog div for the correct library function.

We created workaround where we add class 'g-modal' to size option. But it is not clear solution and if you change this option it won't work for us.

options.size += ' g-modal';

[MisuleT]

Hi @jnizet

I fixed the test and this pull request is ready to merge :)