This update adds the ability to create different rewards for the winner of an arena. I've added an XP reward, a Command reward, a Material (item) reward as well retaining the existing money reward. Different rewards can be set for each arena, or no rewards at all.

There is a new command: /trsetup setreward {arena}
This will start a conversation allowing you set a particular reward (Material, XP or Command) for the arena.
If your arenas have any existing item rewards, these will need to be recreated. Only one itemstack (i.e Material) reward is allowed per arena.
The old command /trsetup setitemsrewards has been removed.

Change to command: /tr list [arena]
With no arguments the /tr list commmand is unchanged and lists all the available arenas. Adding an arena name as an argument will list the configuration settings for that arena, such as max players, timelimit and any rewards that have been set.

Includes the following bug fixes and improvements:

• add a command-reward and an XP-reward option to each arena
• change item rewards to a single material itemstack
• add command /trsetup setrewards {arena} conversation
• remove command /trsetup setitemsrewards
• replace deprecated economy methods to use offlinePlayer
  
• remove overruning firework when player wins
• rename command /trsetup setmoneyrewards to /trsetup setmoneyreward
• add a configuration option to enable/disable fireworks on winning
• refactor firework code using bukkitrunnable
• remove trailing ; separator from final entry in arena list when running /tr list
• add command /tr list <arena> to display arena configuration
• if no rewards are set, don't send empty reward message on win
• check material reward is not null before sending reward message
• check material reward is not null before saving arena
• remove redundant code AddCommandsRewards.java, ClearCommandsRewards.java, SetItemsRewards.java
  
• update /tr help and /tr cmds to display command changes