Addon update

I've changed 'starwars_add' name to 'SWships_add' and updated to version 1.2.
Important! Beside addon name, I've also altered class names. 'Aca_tiev' addon is no more required so I've removed it from needed addons list. For other changes see readme in pack.

I've brought up to date 'Rebel Assault'. It's using now 'SWships_add'. Also I've done minor fixes to scripts in this mission.