What are the stability conditions in the sense of Kontsevich-Soibelman.

I am reading Bridgeland's stability conditions and I've heard people talking about the Kontsevich-Soibelman Stability. I would appreciate a brief introduction on this, in particular my questions are :

What are the Kontsevich-Soibelman Stability conditions ?

How is it related to Bridgeland's Stability (or Douglas' $\pi$ - stability on D-branes) ?

Why do we need to consider Kontsevich-Soibelman stability.

I've to admit my ignorance of the field. Please suggest some references. Thanks.