Post Light sprite fix and state (#8578)

* adjusted post light sprite and added empty state

* update construction location

Resources/Textures/Structures/Lighting/LightPosts/small_light_post.rsi/meta.json

@@ -0,0 +1,20 @@
+{
+  "version": 1,
+  "size": {
+    "x": 32,
+    "y": 32
+  },
+  "license": "CC-BY-SA-3.0",
+  "copyright": "By Peptide90 for SS14",
+  "states": [
+    {
+      "name": "off"
+    },
+    {
+      "name": "on"
+    },
+    {
+      "name": "empty"
+    }
+  ]
+}