Expose access to set_namespace_for_pack, so that callers can use it i…

…n other situations (#23)

Applications might want to enforce automatic namespaces based on certain criteria specific to their package.yml, 
let's say, version: v2, or any other application-specific property. By exposing a public method to do the namespacing,
applications can call this method rather than duplicating the code from this gem.

This change allows applications to hook into the set_namespace_for_pack  method to do any on-demand custom 
namespacing without duplicating the logic defined in this gem.

lib/automatic_namespaces/autoloader.rb

@@ -6,16 +6,20 @@ class AutomaticNamespaces::Autoloader
 
   def enable_automatic_namespaces
     namespaced_packages.each do |pack, metadata|
-      package_namespace = define_namespace(pack, metadata)
-      pack_directories(pack.path, metadata).each do |pack_dir|
-        set_namespace_for(pack_dir, package_namespace)
-      end
+      set_namespace_for_pack(pack, metadata)
+    end
+  end
+
+  def set_namespace_for_pack(pack, metadata)
+    package_namespace = define_namespace(pack, metadata)
+    pack_directories(pack.path, metadata).each do |pack_dir|
+      set_namespace_for_dir(pack_dir, package_namespace)
     end
   end
 
   private
 
-  def set_namespace_for(pack_dir, package_namespace)
+  def set_namespace_for_dir(pack_dir, package_namespace)
     Rails.logger.debug { "Associating #{pack_dir} with namespace #{package_namespace}" }
     ActiveSupport::Dependencies.autoload_paths.delete(pack_dir)
     Rails.autoloaders.main.push_dir(pack_dir, namespace: package_namespace)