Added chapter "Herds" to Gut Instinct

Added the chapter "Herds" to the story Gut Instinct.

For those curious, this story is about Cheerilee having to make a decision during an emergency that affects the life of one of her students, and dealing with the reaction of everpony afterwards. How others read into our decisions -- even if they are arbitrary -- can sometimes affect us in ways we can't imagine at the time.

"Herds" was fun to write, but I had some issues getting it together, particularly with how much the chapter is going to share and how it might further the narrative, hence the stretch between posts for this particular story. Given its placement I didn't want to share a chapter that basically said nothing, working only a transitory piece for the work. I had to brainstorm this one for a bit, and I hope it paid off ^^

Hope everyone reading as enjoyed Gut Instinct as much as I've enjoyed bringing it to you. It's been a blast to write. Also hope everyone affected is keeping warm during this weird cold stretch ^^

Peace