Add possibility to trash all children of current page on "children" tab

[BernhardBaumrock]

Short description of the enhancement

As in PW we often use the page tree and it's hierarchy to store data it would be great to have a "trash all children" button/checkbox on the parent page editor's children tab:

Current vs. suggested behavior

Currently I always have to implement that on my own or use tracy console foreach($page->children as $c) $c->trash()

Why would the enhancement be useful to users?

I think that is a common need and I think that foreach...trash is not the best solution :)

[BernhardBaumrock]

Just realised that TracyDebugger has this feature!