removed buggy files

src/automail/MailItem.java

src/automail/MailPool.java

src/automail/Robot.java

src/exceptions/ExcessiveDeliveryException.java

src/exceptions/ItemTooHeavyException.java

src/exceptions/MailAlreadyDeliveredException.java

src/simulation/Building.java

src/simulation/Clock.java

src/simulation/IMailDelivery.java

src/simulation/MailGenerator.java

src/simulation/Simulation.java