[Initial import
John Meacham <john@repetae.net>**20041203101322] 
[Add test cases and generalized set class
John Meacham <john@repetae.net>**20050109082918] 
[Typo fixes
John Meacham <john@repetae.net>**20050111051324] 
[update for Data.Set
John Meacham <john@repetae.net>**20050219064413] 
[use Data.Map from ghc 6.4
John Meacham <john@repetae.net>**20050321150622] 
[Fix ghc options, code cleanups
John Meacham <john@repetae.net>**20050703144510] 
[fix trailing whitespace
John Meacham <john@repetae.net>**20050809234356] 
[fix up QuickCheck test cases
John Meacham <john@repetae.net>**20050914022741]