containers 0.6.3.1

Bug fixes

• Fix traverse and traverseWithKey for IntMap, which would
  previously produce invalid IntMaps when the input contained
  negative keys (Thanks, Felix Paulusma).

• Fix the traversal order of various functions for Data.IntMap:
  traverseWithKey, traverseMaybeWithKey, filterWithKeyA,
  minimum, maximum, mapAccum, mapAccumWithKey, mapAccumL,
  mapAccumRWithKey, mergeA (Thanks, Felix Paulusma, Simon Jakobi).

Additions

• Add compose for Map and IntMap (Thanks, Alexandre Esteves).

• Add alterF for Set and IntSet (Thanks, Simon Jakobi).

• Add Data.IntSet.mapMonotonic (Thanks, Javran Cheng).

• Add instance Bifoldable Map (Thanks, Joseph C. Sible).

Performance improvements

• Make (<*) for Data.Sequence incrementally asymptotically optimal.
  This finally completes the task, begun in December 2014, of making all
  the Applicative methods for sequences asymptotically optimal
  even when their results are consumed incrementally. Many thanks to
  Li-Yao Xia and Bertram Felgenhauer for helping to clean up and begin
  to document this rather tricky code.

• Speed up fromList and related functions in Data.IntSet, Data.IntMap
  and Data.IntMap.Strict (Thanks, Bertram Felgenhauer).

• Use count{Leading,Trailing}Zeros in Data.IntSet internals (Thanks, Alex
  Biehl).

Other changes

• Reduce usage of the Forest type synonym in Data.Tree (Thanks, David
  Feuer).

• Address a Core lint warning for foldToMaybeTree (Thanks, Matthew Pickering).

• Improve documentation (Thanks to Daniel Wagner, Johannes Waldmann, Steve Mao,
  Gabriel Greif, Jean-Baptiste Mazon, Ziyang Liu, Matt Renaud, Li-Yao Xia).

• Improvements to the testsuite and benchmarks (Thanks, Bertram Felgenhauer,
  Simon Jakobi, Johannes Waldmann).

• Canonicalise Seq's Monoid instance (Thanks, Fumiaki Kinoshita).