Add ^switched-emitter, test in level 4

modules/game/levels/level-4.tmx

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<map version="1.8" tiledversion="1.8.6" orientation="orthogonal" renderorder="right-down" width="20" height="15" tilewidth="16" tileheight="16" infinite="0" nextlayerid="3" nextobjectid="18">
+<map version="1.8" tiledversion="1.8.6" orientation="orthogonal" renderorder="right-down" width="20" height="15" tilewidth="16" tileheight="16" infinite="0" nextlayerid="3" nextobjectid="21">
  <tileset firstgid="1" source="tiles.tsx"/>
  <layer id="1" name="background" width="20" height="15">
   <data encoding="csv">
@@ -10,7 +10,7 @@
 23,24,24,24,24,24,24,24,24,24,24,24,24,24,24,23,24,24,24,23,
 23,24,24,24,24,49,3,24,3,24,24,24,24,24,24,23,24,28,24,23,
 23,24,24,24,24,24,24,24,24,24,3,24,24,24,24,23,24,24,24,23,
-23,24,24,24,24,49,3,3,3,24,24,24,3,24,24,24,24,24,24,23,
+23,24,24,24,24,48,3,3,3,24,24,24,3,24,24,24,24,24,24,23,
 23,24,24,24,24,24,24,24,24,24,3,24,24,24,24,23,24,24,24,23,
 23,24,49,3,3,24,3,3,3,24,24,24,24,24,24,23,24,24,24,23,
 23,24,24,24,24,24,24,24,24,24,24,24,24,24,24,23,24,24,24,23,
@@ -37,5 +37,11 @@
   <object id="13" type="xor-gate" gid="45" x="144" y="96" width="16" height="16"/>
   <object id="15" type="and-gate" gid="43" x="176" y="112" width="16" height="16"/>
   <object id="17" type="or-gate" gid="44" x="144" y="128" width="16" height="16"/>
+  <object id="18" type="floor-switch" gid="25" x="112" y="48" width="16" height="16">
+   <properties>
+    <property name="target-x" type="int" value="5"/>
+    <property name="target-y" type="int" value="7"/>
+   </properties>
+  </object>
  </objectgroup>
 </map>

modules/game/levels/tiles.tsx

@@ -12,6 +12,7 @@
   </properties>
  </tile>
  <tile id="27" type="exit"/>
+ <tile id="47" type="switched-emitter"/>
  <tile id="48" type="clock-emitter"/>
  <tile id="80" type="wall">
   <properties>