Changed the drop system to a two steps system: First the game chooses the...

Changed the drop system to a two steps system: First the game chooses the quality of the item (unique, double greater, greater, ...) and then the actual object is selected. Quality chance varies by levels and by drop source (bosses obviously drop better stuff).


git-svn-id: http://svn.net-core.org/repos/t-engine4@2954 51575b47-30f0-44d4-a5cc-537603b46e54