Tone down scare monster by excluding humans and uniques

Scroll of scare monster completely shut down most of the actual
challenging monsters, such as uniques. Tone it down, so you can
use it to ignore the smaller threats while dealing with uniques,
or get most of the effect in the early game when you're usually
dealing with normal monsters.

doc/fixes37.0

@@ -77,6 +77,7 @@ inventory cursing caused by "this water's no good" effect when drinking from
 	a fountain didn't update persistent inventory window
 fix priest created inside temple wall
 fix vault guard occasionally encasing monsters in stone
+tone down scare monster by excluding humans and uniques
 
 
 Fixes to 3.7.0-x Problems that Were Exposed Via git Repository

src/monmove.c

@@ -135,10 +135,13 @@ int x, y;
 struct monst *mtmp;
 {
     /* creatures who are directly resistant to magical scaring:
+     * humans aren't monsters
+     * uniques have ascended their base monster instincts
      * Rodney, lawful minions, Angels, the Riders, shopkeepers
      * inside their own shop, priests inside their own temple */
     if (mtmp->iswiz || is_lminion(mtmp) || mtmp->data == &mons[PM_ANGEL]
         || is_rider(mtmp->data)
+        || mtmp->data->mlet == S_HUMAN || unique_corpstat(mtmp->data)
         || (mtmp->isshk && inhishop(mtmp))
         || (mtmp->ispriest && inhistemple(mtmp)))
         return FALSE;