search_menu places module name in path. Path segment should come from hook_search.

The current implementation of search_menu places the implementing module name in the path. Examples are search/node and search/user. This has several implications. First, there is no control over this path, ie no way to say that content search should be search/content (let's ignore hook_menu_alter here), and second, there is no way for 1 module to define multiple search paths and handle them.

My proposed solution is to let hook_search return its path(s) in a new $op, called 'paths'.