Allow editor role to use some plugins

Hello , if any one could please to figure out how can I give the editor role permission to use some plugins.

I have edited the admin bar already and removed all the items i dont want to editor rode (client) to have. But now im nor really sure on how get some plugins I use to be visible for the cleints account.
The plugins I need for the editor role to have access to are :
gravity forms
and the new_royalslider.

I have been avoiding plugins for any solution and rather do it via functions.php, for two reasosn . 1- is to learn how to and the other reason is beacuse the less plugins the better on the server. This client uses a dodgy server and he wont change so i have to make the most with the limitations i have, hence run everythig through the funtions.php .

HELP and CHEERS 😀