Fix some Javadoc warnings

src/main/java/org/bukkit/entity/AbstractHorse.java

@@ -14,7 +14,7 @@ public interface AbstractHorse extends Animals, Vehicle, InventoryHolder, Tameab
      * Whether a horse is a regular horse, donkey, mule, or other kind of horse
      * is determined using the variant.
      *
-     * @return a {@link Variant} representing the horse's variant
+     * @return a {@link Horse.Variant} representing the horse's variant
      * @deprecated different variants are different classes
      */
     @Deprecated

src/main/java/org/bukkit/entity/EntityType.java

@@ -42,7 +42,7 @@ public enum EntityType {
      */
     WITHER_SKELETON("wither_skeleton", WitherSkeleton.class, 5),
     /**
-     * @See Stray
+     * @see Stray
      */
     STRAY("stray", Stray.class, 6),
     /**

src/main/java/org/bukkit/entity/Horse.java

@@ -144,7 +144,7 @@ public interface Horse extends AbstractHorse {
     public void setStyle(Style style);
 
     /**
-     * @return
+     * @return carrying chest status
      * @deprecated see {@link ChestedHorse}
      */
     @Deprecated

src/main/java/org/bukkit/entity/Zombie.java

@@ -43,7 +43,7 @@ public interface Zombie extends Monster {
     public void setVillagerProfession(Villager.Profession profession);
 
     /**
-     * @return 
+     * @return profession
      * @see ZombieVillager#getVillagerProfession()
      */
     @Deprecated