Merge pull request #274 from madelson/release-2.8.1

Release 2.8.1

Merge pull request #268 from madelson/release-2.8

Release 2.8

Merge pull request #257 from madelson/release-2.7.1

Release 2.7.1

Merge pull request #252 from madelson/release-2.7

Release 2.7

Merge pull request #239 from madelson/release-2.6

Release 2.6

Merge pull request #232 from madelson/release-2.5.1

Release 2.5.1

Merge pull request #220 from madelson/release-2.5

Release 2.5

Merge pull request #200 from madelson/release-2.4

Release 2.4

2.3.4 release

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