Two weapon fighting:
When you take the Attack action and attack with a light melee weapon that you're holding in one hand, you can use a bonus action to attack with a different light melee weapon that you're holding in the other hand. -PHB 195
Pact of the chain feature:
Additionally, when you take the Attack action, you can forgo one of your own attacks to allow your familiar to make one attack of its own. -PHB 107
If I attack with a short sword, can I direct my familiar to make an attack in place of my second bonus-action attack?
If you have enough Fighter levels, you get more than one attack from your Attack Action, so could forfeit one to let your Familiar attack, and use the rest yourself.
Fighter's Extra Attack feature: (PBR 25)
But, two-weapon fighting doesn't give you extra attacks as part of an Attack Action, it gives you an attack as a Bonus Action. And, you don't get that Bonus Action unless you attack with your other hand first.
Two-Weapon Fighting: (PBR 74)
Bonus actions: (PBR 69)
(Quotes are from Player's Basic Rules v0.2)