Added a route helper

This addition helps devs i.e theme developers to match if a route with a sub_route(s) i.e page/contact is current than the current index request from G\get_route_name(); // page

<?php if(G\get_route_name() == 'explore') { ?> current<?php } ?>"> // True
<?php if(G\get_route_name() == 'page') { ?> current<?php } ?>"> // True
<?php if(G\get_route_name() == 'page/contact') { ?> current<?php } ?>"> // False /contact is array in page

<?php if(G\Handler::getMappedRoute() == 'page/contact') { ?> class="current"<?php } ?> //True array is now string to match with /