Fix test warnings
Rename GameMaster#stage_ary to #stage_history

This is more descriptive of what is held.
Use reduce (inject) more functionally

This replaces work done in the block with a separate map.

Enumerable#reduce used to satisfy @aasmith (fishermanchips on twitter)
Improve the look of GameMaster#game_rundown

This is purely cosmetic, but makes the method easier to read.
Remove unused Client::default_name method
Fixup whitespace