[php] (change:minor) Added safety checks/initializations for unset or null variables. Also, replaced use of 'unregister_session' with 'unset($_SESSION[...])'.
[php] (change:minor) Added default timezone to quiet PHP warnings.
[php] (change:minor) Initialized variable.
[php] (change:minor) Added safety checks/initializations for unset or null variables. Also, replaced use of 'unregister_session' with 'unset($_SESSION[...])'.
[php] (change:minor) Added safety checks/initializations for unset or null variables. Also, replaced use of 'unregister_session' with 'unset($_SESSION[...])'.
[php] (change:minor) Added safety checks/initializations for unset or null variables. Also, replaced use of 'unregister_session' with 'unset($_SESSION[...])'.