Announcing containers 0.5.8.2, 0.5.9.2, and 0.5.10.1

[David Feuer]

I had not planned to make any additional releases before GHC 8.2, but
bugs forced my hand. In particular, Tom Smalley discovered major bugs
in Data.IntMap.restrictKeys and Data.IntMap.withoutKeys. A mistake I
made adding those functions to the test suite prevented the problem
from being discovered. This affects both 0.5.8.1 and 0.5.9.1, both of
which are now deprecated. I believe both the functions and the test
suite are now working as intended.

In a less frightening bug fix, Ryan Scott fixed a discrepancy between
the Show1 instance for Data.Tree and its Show instance. This affected
version 0.5.9.1. I also fixed misdirected Haddock links in 0.5.9.1.

Version 0.5.10.1 comes with one new feature: Data.Sequence has a
MonadZip instance.

Thanks also to Simon Jakobi for removing the meaningless stability annotations.

David Feuer