Ah salvage. Yes it is in trinity.
I am going by memory here but in the menu items(or of its sub menu's) you will find something that looks like this:
----------------- Vendor ---------Salvage
Magic ------------- . -----------------0
Rare ------------- . -----------------0
Legendary -------. --------------- 0
Now by default it is set on vendor use the button to make it salvage. You can't miss it.