Essentials Group manager and permissions

On my server, I use permissions for everything, however I am sick of FTPing the server and reloading permissions everytime someone wants to buy an upgrade to a group called merchant.

I have read about essentials group manager, but Im a little confused. Basically I want a way to edit the permissions from using a command ingame (I have tried permissionsplus but its incompatible with my server)

Does essentials hook into permissions or replace it entirely? What is the best way to do it?

Anyone?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Don't use GroupManager, its way outdated and the creators are considering deleting it in favor of Permissions. What do you mean permissionsplus in "incompatible"? You have an outdated CB version?

 

http://forums.bukkit.org/threads/admn-dev-permissions-3-1-6-the-plugin-of-tomorrow-935.18430/
Check out the youtube video under the Install Spoiler, He shows you how to use ingame commands for permissions.... If thats what you were asking for.