Merge pull request #138 from bgamari/wip/bump-base

Bump base upper bound to 4.15

unix.cabal

@@ -62,7 +62,7 @@ library
         buildable: False
 
     build-depends:
-        base        >= 4.5     && < 4.14,
+        base        >= 4.5     && < 4.15,
         bytestring  >= 0.9.2   && < 0.11,
         time        >= 1.2     && < 1.10