Fix crewmates being drawn behind other entities

This fixes the draw order by drawing all other entities first, before
then drawing all humanoids[1] after, including the player afterwards.

This is actually a regression fix from #191. When I was testing this, I
was thinking about where get a crewmate in front of another entity in
the main game, other than the checkpoints in Intermission 1. And then I
thought about the teleporters, because I remember the pre-Deep Space
cutscene in Dimension Open looking funny because Vita ended up being
behind the teleporter. (Actually, a lot of the cutscenes of Dimension
Open look funny because of crewmates standing behind terminals.)

So then I tried to get crewmates in front of teleporters. It actually
turns out that you can't do it for most of them... except for Verdigris.
And then that's what I realized why there was an oddity in WarpClass.cpp
when I was removing the `active` system from the game - for some reason,
the game put a hole in `obj.entities` between the teleporter and the
player when loading the room Murdering Twinmaker. In a violation of
Chesterton's Fence (the principle that you should understand something
before removing it), I shrugged it off and decided "there's no way to
support having holes with my new system, and having holes is probably
bad anyway, so I'm going to remove this and move on". The fact that
there wasn't any comments clarifying the mysterious code didn't help
(but, this *was* 2.2 code after all; have you *seen* 2.2 code?!).

And it turns out that this maneuver was done so Verdigris would fill
that hole when he got created, and Verdigris being first before the
teleporter would mean he would be drawn in front of the teleporter,
instead of being behind it. So ever since
b1b1474b7b got merged, there has actually
been a regression from 2.2 where Verdigris got drawn behind the
teleporter in Murdering Twinmaker, instead of properly being in front of
it like in 2.2 and previous.

This patch fixes that regression, but it actually properly fixes it
instead of hacking around with the `active` system.

Closes #426.

[1]: I'm going to go on a rant here, so hear me out. It's not explicitly
stated that the characters in VVVVVV are human. So, given this
information, what do we call them? Well, the VVVVVV community (at least
the custom levels one, I don't think the speedrunning community does
this or is preoccupied with lore in the first place) decided to call
them "villis", because of the roomname "The Villi People" - which is
only one blunder in a series of awful headcanons based off of the
assumption that the intent of Bennett Foddy (who named the roomnames)
was to decree some sort of lore to the game. Another one being
"Verdigris can't flip" because of "Green Dudes Can't Flip". Then an OC
(original character) got named based off of "The Voon Show" too. And so
on and so forth.

desktop_version/src/Graphics.cpp

@@ -1595,9 +1595,30 @@ void Graphics::drawentities()
 {
     const int yoff = map.towermode ? lerp(map.oldypos, map.ypos) : 0;
 
-    for (int i = obj.entities.size() - 1; i >= 0; i--)
+    if (!map.custommode)
     {
-        drawentity(i, yoff);
+        for (int i = obj.entities.size() - 1; i >= 0; i--)
+        {
+            if (!obj.entities[i].ishumanoid())
+            {
+                drawentity(i, yoff);
+            }
+        }
+
+        for (int i = obj.entities.size() - 1; i >= 0; i--)
+        {
+            if (obj.entities[i].ishumanoid())
+            {
+                drawentity(i, yoff);
+            }
+        }
+    }
+    else
+    {
+        for (int i = obj.entities.size() - 1; i >= 0; i--)
+        {
+            drawentity(i, yoff);
+        }
     }
 }