Implement cloneArray and cloneMutableArray for GHC >= 7.2.1
Add fallback function for cloneArray and cloneMutableArray for GHC < 7.2.1
Oops, the CPP constant for GLASGOW_HASKELL in 7.2 should be 702, per https://ghc.haskell.org/trac/ghc/ticket/6023
Merge pull request #7 from jberryman/master

Implement cloneArray and cloneMutableArray for GHC >= 7.2.1