Changing Rake namespace to "debshots"

Let's group all debshots-related Rake tasks under a common namespace

lib/tasks/screenshots_to_paperclip.rake

@@ -1,3 +1,4 @@
+namespace :debshots do
   desc "Convert images from the original screenshots directory tree to paperclip-styled images"
 
   task :screenshots_to_paperclip => :environment do
@@ -30,3 +31,4 @@ task :screenshots_to_paperclip => :environment do
       end
     end
   end
+end