v3.0.0

• All cssnano plugins and cssnano itself have migrated to PostCSS 5.x. Please
  make sure that when using the 3.x releases that you use a 5.x compatible
  PostCSS runner.
• cssnano will now compress inline SVG through SVGO. Because of this change,
  interfacing with cssnano must now be done through an asynchronous API. The
  main process method has the same signature as a PostCSS processor instance.
• The old options such as merge & fonts that were deprecated in
  release 2.5.0 were removed. The new architecture allows you to specify any
  module name to disable it.
• postcss-minify-selectors' at-rule compression was extracted out into
  postcss-minify-params (thanks to @TrySound).
• Overall performance of the module has improved dramatically, thanks to work
  by @TrySound and input from the community.
• Improved selector merging/deduplication in certain use cases.
• cssnano no longer compresses hex colours in filter properties, to better
  support old versions of Internet Explorer (thanks to @faddee).
• cssnano will not merge properties together that have an inherit keyword.
• postcss-minify-font-weight & postcss-font-family were consolidated into
  postcss-minify-font-values. Using the old options will print deprecation
  warnings (thanks to @TrySound).
• The cssnano CLI was extracted into a separate module, so that dependent
  modules such as gulp-cssnano don't download unnecessary extras.

v2.6.1

• Improved performance of the core module functionOptimiser.

v2.6.0

• Adds a new optimisation which re-orders properties that accept values in
  an arbitrary order. This can lead to improved merging behaviour in certain
  cases.

v2.5.0

• Adds support for disabling modules of the user's choosing, with new option
  names. The old options (such as merge & fonts) will be removed in 3.0.

v2.4.0

• postcss-minify-selectors was extended to add support for conversion of
  ::before to :before; this release removes the dedicated
  postcss-pseudoelements module.

v2.3.0

• Consolidated postcss-minify-trbl & two integrated modules into
  postcss-merge-longhand.

v2.2.0

• Replaced integrated plugin filter with postcss-filter-plugins.
• Improved rule merging logic.
• Improved performance across the board by reducing AST iterations where it
  was possible to do so.
• cssnano will now perform better whitespace compression when used with other
  PostCSS plugins.

v2.1.1

• Fixes an issue where options were not passed to normalize-url.
• Fixed an integration issue with postcss-font-magician.
• Fixed incorrect conversion of some numeric values.
• Fixed an issue that caused incorrect animation removal in some cases.

v2.1.0

• Allow postcss-font-family to be disabled.

v2.0.3

• cssnano can now be consumed with the parentheses-less method in PostCSS; e.g.
  postcss([ cssnano ]).
• Fixes an issue where 'Din' was being picked up by the logic as a numeric
  value, causing the full font name to be incorrectly rearranged.