Modal-header default closeButton has no type='button' causing forms to treat it as a submit incorrectly

[wanderingcoder2]

the default closeButton for modal-header renders as <button class="close" aria-label="Close Modal"><span aria-hidden="true">×</span></button>

can you please change the default to type="button" so it would be:
<button type="button" class="close" aria-label="Close Modal"><span aria-hidden="true">×</span></button>

When using forms this button is treated as a submit incorrectly because the type was never specified and the default for many browsers is 'submit'

[jquense]

happy to take a PR!

[wanderingcoder2]

Ill try to get one that works i was having a difficult time figuring out how to assign properties to the button under the current architecture looking in both modal and dismiss areas and the bootstrap files, hopefully I will find a fix this weekend even if i have to re-architect a few things. If you have insights that would help I welcome them so a PR can get done faster, I am not as well versed as I would like with this project, that's why i posted a bug report figuring someone else may know how to do it already (and to make sure if i did find it a PR was ok).