!! Collapsable Boxes

This [Wiki.Style] is an extension of [How To Create Collapsable Lists].
It provides collapsable boxes : when closed only the title of the box is visible; 
when opened the complete box becomes visible. A open/close icon will be shown
at the right edge of the box, indicating the status of the box.

This is very convenient for info in pages like 
LeftMenu, LeftMenuFooter, your <username>Favorites, and so on.

! Usage

{{{
  %%collapsebox
  ! Title of the box
  Here is the body of the box
  * item 1
  * item 2
  %%
}}}

Reality check:

%%collapsebox
! Box1
Here is the body of the box
* item 1
* item 2
%%