0.2.11.0

• Add HashMap.findWithDefault (soft-deprecates HashMap.lookupDefault).
  Thanks, Matt Renaud.

• Add HashMap.fromListWithKey. Thanks, Josef Svenningsson.

• Add more folding functions and use them in Foldable instances. Thanks,
  David Feuer.

• Add HashMap.!?, a flipped version of lookup. Thanks, Matt Renaud.

• Add a Bifoldable instance for HashMap. Thanks, Joseph Sible.

• Add a HasCallStack constraint to (!). Thanks, Roman Cheplyaka.

Bug fixes

• Fix a space leak affecting updates on keys with hash collisions. Thanks,
  Neil Mitchell. (#254)

• Get rid of some silly thunks that could be left lying around. (#232).
  Thanks, David Feuer.

Other changes

• Speed up the Hashable instances for HashMap and HashSet. Thanks,
  Edward Amsden.

• Remove a dependency cycle hack from the benchmark suite. Thanks,
  Andrew Martin.

• Improve documentation. Thanks, Tristan McLeay, Li-yao Xia, Gareth Smith,
  Simon Jakobi, Sergey Vinokurov, and likely others.