[BUG] Nested Maximized Cards - min/max icons are replaced also in children cards

[edallocco]

If you use nested cards everyone with maximize widget, when you maximize the parent card, also the widget-icon of the children get replace.

The aspected behaviour is the icon to be linked to this card only; to obtain that i've change adminlte.js at line 281
from
this._parent.find(this._settings.maximizeTrigger + " ." + this._settings.maximizeIcon).addClass(this._settings.minimizeIcon).removeClass(this._settings.maximizeIcon);
to
this._parent.find(this._settings.maximizeTrigger + " ." + this._settings.maximizeIcon).first().addClass(this._settings.minimizeIcon).removeClass(this._settings.maximizeIcon);

and the result is: