Battle UFO: polish drops

- Whip
  - Player gets power-up instantly, no paper item spawned
- Items
  - Put a small delay on the drop appearing
  - Adjusted drop spawn position so it spawns right under
    the UFO

src/k_powerup.cpp

@@ -50,6 +50,8 @@ void K_GivePowerUp(player_t* player, kartitems_t powerup, tic_t time)
 		Obj_SpawnPowerUpAura(player);
 	}
 
+	player->flashing = 2*TICRATE;
+
 	switch (powerup)
 	{
 	case POWERUP_SMONITOR:

src/objects/battle-ufo.cpp

@@ -12,6 +12,7 @@
 #include "../p_local.h"
 #include "../k_battle.h"
 #include "../k_objects.h"
+#include "../k_powerup.h"
 #include "../k_kart.h"
 #include "../k_hud.h" // K_AddMessage
 
@@ -151,26 +152,30 @@ void Obj_BattleUFODeath(mobj_t *mobj, mobj_t *inflictor)
 {
 	UFO* ufo = static_cast<UFO*>(mobj);
 	const SINT8 flip = P_MobjFlip(ufo);
+	const kartitems_t pwrup = static_cast<kartitems_t>(P_RandomRange(PR_BATTLEUFO, FIRSTPOWERUP, LASTPOWERUP));
 
 	ufo->momz = -(8*mapobjectscale)/2;
 
-	mobj_t* drop = K_CreatePaperItem(
-		ufo->x,
-		ufo->y,
-		ufo->z + (flip),
-		0,
-		flip,
-		P_RandomRange(PR_BATTLEUFO, FIRSTPOWERUP, LASTPOWERUP),
-		BATTLE_POWERUP_TIME
-	);
-
-	if (!P_MobjWasRemoved(inflictor) && inflictor->type == MT_INSTAWHIP)
+	if (!P_MobjWasRemoved(inflictor) && inflictor->type == MT_INSTAWHIP &&
+		!P_MobjWasRemoved(inflictor->target) && inflictor->target->player)
 	{
-		// Take momentum of player who whips
-		inflictor = inflictor->target;
+		// Just give it to the player, they earned it.
+		K_GivePowerUp(inflictor->target->player, pwrup, BATTLE_POWERUP_TIME);
 	}
+	else
+	{
+		mobj_t *drop = K_CreatePaperItem(
+			ufo->x,
+			ufo->y,
+			ufo->z + ufo->sprzoff() + (flip),
+			0,
+			flip,
+			pwrup,
+			BATTLE_POWERUP_TIME
+		);
 
-	drop->momz = !P_MobjWasRemoved(inflictor) ? inflictor->momz : 0;
+		drop->hitlag = ufo->hitlag();
+	}
 
 	if (ufo->spawner())
 	{

src/p_inter.c

@@ -402,7 +402,6 @@ void P_TouchSpecialThing(mobj_t *special, mobj_t *toucher, boolean heightcheck)
 					return;
 
 				K_GivePowerUp(player, special->threshold, special->movecount);
-				player->flashing = 2*TICRATE;
 			}
 			else
 			{