doc: Make all module docs self-contained

doc_classes/VisualScriptSelf.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<class name="VisualScriptSelf" inherits="VisualScriptNode" category="Core" version="3.0-alpha">
+	<brief_description>
+		Outputs a reference to the current instance.
+	</brief_description>
+	<description>
+		Provides a reference to the node running the visual script.
+		[b]Input Ports:[/b]
+		none
+		[b]Output Ports:[/b]
+		- Data (object): [code]instance[/code]
+	</description>
+	<tutorials>
+	</tutorials>
+	<demos>
+	</demos>
+	<methods>
+	</methods>
+	<constants>
+	</constants>
+</class>