Pacts of Friendship/Secrecy were removed and replaced with Declarations of Friendship and Denunciation. Basically, the entire idea now is to declare your friends and then become friends with similar people (being friends with those who are friends with each other will reinforce things).
While I don't miss the actual declaration of secrecy (they never seemed to conspire much against the civ you're supposed to be conspiring against). However, I do wish you could request that a civ denounce or make friends with a third party civ.