fix naming conflict between SQLite3::Module and ::Module

Author: lionelperrin

lib/sqlite3/database.rb

@@ -393,7 +393,7 @@ def self.finalize( &block )
       end
 
       proxy = factory.new
-      proxy.extend(Module.new {
+      proxy.extend(::Module.new {
         attr_accessor :ctx
 
         def step( *args )