Adds the Improvised Shotgun (#18025)

* improvised shotguns

* spaghetti

* progress so far (TODO: rename modular_reciever.yml)

* i forgotted

* everything so far

* fuck fuck fuck (boner boner)

* ganon: You must die

* bobie

* boob boob booby balls

Resources/Textures/Objects/Weapons/Guns/Shotguns/improvised_shotgun.rsi/meta.json

@@ -0,0 +1,32 @@
+{
+  "version": 1,
+  "license": "CC-BY-SA-3.0",
+  "copyright": "Taken/modified from https://github.com/tgstation/tgstation/ at commit fb2d71495bfe81446159ef528534193d09dd8d34, inhand and back sprites modified by Flareguy",
+  "size": {
+    "x": 32,
+    "y": 32
+  },
+  "states": [
+    {
+      "name": "icon"
+    },
+	{
+      "name": "inhand-left",
+      "directions": 4
+	},
+	{
+	  "name": "inhand-right",
+	  "directions": 4
+	},
+    {
+      "name": "equipped-BACKPACK",
+      "directions": 4
+    },
+    {
+      "name": "ishotgunstep1"
+    },
+    {
+      "name": "ishotgunstep2"
+    }
+  ]
+}