Update about.tpl
Update about.tpl

licence text change to AGPL 3.0.
timnboys/Feathur,Feathur/Feathur,SDenny/Feathur,Feathur/Feathur,zvenzzon/Feathur,timnboys/Feathur,zvenzzon/Feathur,timnboys/Feathur,Feathur/Feathur,SDenny/Feathur,zvenzzon/Feathur,SDenny/Feathur,timnboys/Feathur,zvenzzon/Feathur,Feathur/Feathur,timnboys/Feathur,SDenny/Feathur,Feathur/Feathur,zvenzzon/Feathur