Add Sarnia to the Search API contextual links

Sarnia pages are not added to the contextual links for servers at admin/config/search/search_api. This is easily remedied by adding 'context' => MENU_CONTEXT_INLINE | MENU_CONTEXT_PAGE, to the page information in sarnia_menu().

For comparison, see the search_api_solr module's implementation. It does the same thing to add its Files page to the contextual links. Also, see the hook_menu() documentation.

Remember to clear the menu cache after applying the patch.