How do I change diplomacy besides war and vassals? (open borders, defensive pacts...)

[Genghis Khaiser]

I was messing around with the World Builder in a game, believing I had the game won, and made my ally (I was playing a mod, so it may be closer to a defensive pact) my vassal. When I realized I was wrong, I unvassalized him, but we were no longer allies. I want to restore that alliance but I can't find how. Where do I configure diplomacy things like open borders, defensive pacts, and such?

 

[Tholal]

You probably want this add-on

http://forums.civfanatics.com/showthread.php?t=491837