Update Godot versions

Godot 3.2 released Jan 29th

After discussion in IRC remove 3.0 and 3.1 docs as almost nobody uses
3.0 anymore and 3.2 docs are mostly compatable with 3.1

lib/docs/scrapers/godot.rb

@@ -28,18 +28,13 @@ module Docs
       end
     end
 
-    version '3.1' do
-      self.release = '3.1.1'
-      self.base_url = "http://docs.godotengine.org/en/#{self.version}/"
-    end
-
-    version '3.0' do
-      self.release = '3.0.6'
+    version '3.2' do
+      self.release = '3.2.1'
       self.base_url = "http://docs.godotengine.org/en/#{self.version}/"
     end
 
     version '2.1' do
-      self.release = '2.1'
+      self.release = '2.1.6'
       self.base_url = "http://docs.godotengine.org/en/#{self.version}/"
     end