User groups feature initial commit.

git-svn-id: http://redmine.rubyforge.org/svn/branches/work@1373 e93f8b46-1217-0410-a6f0-8f06a7374b81

groups/db/migrate/093_create_groups.rb

@@ -0,0 +1,11 @@
+class CreateGroups < ActiveRecord::Migration
+  def self.up
+    create_table :groups do |t|
+      t.column :name, :string, :null => false
+    end
+  end
+
+  def self.down
+    drop_table :groups
+  end
+end

groups/db/migrate/094_add_users_group_id.rb

@@ -0,0 +1,9 @@
+class AddUsersGroupId < ActiveRecord::Migration
+  def self.up
+    add_column :users, :group_id, :integer
+  end
+
+  def self.down
+    remove_column :users, :group_id
+  end
+end

groups/db/migrate/095_change_members_users_association_to_polymorphic.rb

@@ -0,0 +1,20 @@
+class ChangeMembersUsersAssociationToPolymorphic < ActiveRecord::Migration
+  def self.up
+    add_column :members, :principal_type, :string
+    add_column :members, :principal_id, :integer
+    add_column :members, :inherited_from, :integer
+    Member.update_all "principal_type = 'User', principal_id = user_id"
+    remove_column :members, :user_id
+    add_index :members, [:principal_type, :principal_id], :name => :members_principal
+  end
+
+  def self.down
+    # Remove inherited memberships
+    Member.delete_all "inherited_from IS NOT NULL"
+    add_column :members, :user_id, :integer, :default => 0, :null => false
+    Member.update_all "user_id = principal_id"
+    remove_column :members, :principal_type, :string
+    remove_column :members, :principal_id, :integer
+    remove_column :members, :inherited_from, :integer
+  end
+end