Change "Liver Chestnut" To "Sooty Chestnut"

There is a technically inaccurate coat color description on EV given to chestnut horses with a Sooty gene. They get labeled as "Liver Chestnut", which is, well, a very different thing genetics-wise x) I believe we don't have a corresponding artwork for liver chestnut horses, but if we did, Liver Chestnut color should've been given to [ee aa] horses, regardless if Sooty is present. And [ee AA/Aa] horses with [STYsty/STYSTY] are just sooty chestnuts, not liver. So let us change the descriptions accordingly, hope it should be an easy fix :)

I support this if horse shades are added and names are assigned to those shades. 

 I think the combination of sooty+chestnut making liver was originally added because it was a common theory at the time of the recode (2016ish) and because there are no shade differences in game currently. Even if it's not completely true/accurate.