Compatibility update for lens-4.4

Changes to the way makeClassy worked make hyperloglog's old
implementation incompatible with makeClassy in 4.4. While
changes to this are in the works, they won't be ready until 4.5.
Manually implementing the bits that were previously implemented
with Template Haskell will allow users to proceed using lens-4.4
Merge pull request #7 from glguy/th-removal-lens44

Compatibility update for lens-4.4