What exactly are the bonuses the AI gets at each difficulty level in civ5?

In Civilization 5, the game states that the AI gets significant bonuses to their play at the higher difficulty levels. I have been unable to find what exactly those bonuses are. I have heard rumors that on Deity, for example, the AI starts with 3 settlers, 6 warriors, and doesn't have a happiness cap at all.

Can anyone clarify with details?

There are too many things to list out here, but you can find the answers in the CIV5HandicapInfos.xml file in your \Steam\steamapps\common\sid meier's civilization v\Assets\Gameplay\XML\GameInfo folder. For example, Deity lists that the AI starts with two defensive units (warriors), two workers, and one scout. Another part of that file lists the free techs for you or the AI. On Deity, the AI starts with The Wheel, Mining, Animal Husbandry, and Pottery.