4.0.0-rc.0

• Breaking: Drops support for Node 0.12, we now require at least Node 4.
• Breaking: Update PostCSS to 6.0.0.

2.1.0

• Now supports discarding duplicates irrespective of property order, better
  support for legacy hacks & partial duplicate removal (thanks to @andyjansson).

2.0.2

• Major performance boost by lessening algorithmic complexity; each node is
  now cached and the nested loop removed, meaning that each node is cast to a
  string only once (thanks to @asztal).

2.0.1

• Now compiled with babel 6.
• Minor performance boost from exiting from the dedupe function if the node
  has less than two child nodes.

2.0.0

• Upgraded to PostCSS 5.

1.2.1

• Fixes an integration test failure with cssnano; use PostCSS each rather
  than native forEach (thanks to @TrySound).

1.2.0

• Improved duplicate detection (thanks to @TrySound).

1.1.6

• Improved performance by caching string representations of nodes, and
  minimising stringifying as much as possible (thanks to @TrySound).

1.1.5

• Fixed an issue where comments were being deduplicated.

1.1.4

• Improved performance by making all AST iterations in a single pass.

1.1.3

• Improved documentation for compatibility with the plugin guidelines.
• Simplify main source code.

1.1.2

• Fixed an issue where declarations inside similar keyframes were being
  discarded incorrectly.

1.1.1

• Fixed a bug where keyframe rules were being incorrectly discarded, if they had
  the same declarations but different vendor prefixes.

1.1.0

• Now uses the PostCSS 4.1 plugin API.

1.0.0

• Initial release.