data-replace-closest (improvement to naming)

[brycenesbitt]

This is more a suggestion than an issue report.
I'm usually the programmer who delves into fixing the messy bugs in legacy code. As such I've read a lot of code. Imagine if instead of

<class="form ajax"  data-replace="#message-form"...>

It read:

<class="form ajax" data-ajax-replace="#message-form"...>

Then even to someone not familiar with eldarion-ajax, it would be pretty clear the class and the replacement are connected.