Merge pull request #31 from hvr/pr/semigroup
authorDavid Terei <github@davidterei.com>
Sat, 6 Feb 2016 21:02:12 +0000 (13:02 -0800)
committerDavid Terei <github@davidterei.com>
Sat, 6 Feb 2016 21:02:12 +0000 (13:02 -0800)
Define Semigroup instances for base>=4.9


Trivial merge