# Adds an item at the end of the menu. Available options:
# * param: the parameter name that is used for the project id (default is :id)
# * if: a Proc that is called before rendering the item, the item is displayed only if it returns true
# * caption that can be:
# * a localized string Symbol
# * a String
# * a Proc that can take the project as argument
# * before, after: specify where the menu item should be inserted (eg. :after => :activity)
# * parent: menu item will be added as a child of another named menu (eg. :parent => :issues)
# * children: a Proc that is called before rendering the item. The Proc should return an array of MenuItems, which will be added as children to this item.