Modified PC_plugin_login_form_widget widget to use page reference id instead of plugin name to find pages responsible for registering and password changing.
Added $remind_username_link variable to PC_plugin_login_form_widget widget views.
Removed $errors variable from PC_plugin_login_form_widget widget views since validation was actually useless.
Added check to PC_user class so that when trying to login with empty username and/or password it will set it's login error as if an invalid username/password error occured.