Menu urls like /categories/новости-проекта would turn into /categories/d0bdd0bed0b2d0bed181d182d0b8-d0bfd180d0bed0b5d0bad182d0b0, which is illegal, while the directory under the categories/ is created with the original name. It results in 404 not found error.
This commit fixes that by make sure that SanitizeUrl() is called last.
Fixes#719
Prior to this commit, `HasMenuCurrent` and `IsMenuCurrent` on `Node` always returned false.
This made it hard (if possible at all) to mark the currently selected menu item/group for non-Page content (home page, category pages etc.), i.e. for menus defined in the site configuration.
This commit provides an implementation of these two methods.
Notable design choices:
* These menu items have a loose coupling to the the resources they navigate to; the `Url` is the best common identificator. To facilitate a consistent matching, and to get it in line with the menu items connected to `Page`, relative Urls (Urls starting with '/') for menu items in the site configuration are converted to permaLinks using the same rules used for others’.
* `IsMenuCurrent` only looks at the children of the current node; this is in line with the implementation on `Page`.
* Due to this loose coupling, `IsMenuCurrent` have to search downards in the tree to make sure that the node is inside the current menu. This could have been made simpler if it could answer `yes` to any match of any menu item matching the current resource.
This commit also adds a set of unit tests for the menu system.
Fixes#367
