v4.0.0-rc.2

Features

• Includes the new release candidate for postcss-selector-parser 3.
• Refactors comments tokenizing in postcss-discard-comments to be more
  memory efficient.
• Adds css-declaration-sorter for improved gzip compression efficiencies
  (thanks to @Siilwyn).
• postcss-svgo now optimises base 64 encoded SVG where possible
  (thanks to @evilebottnawi).
• stylehacks now supports @media \0screen\,screen\9 {} hacks
  (thanks to @evilebottnawi).

Bug Fixes

• Fixed handling of package.json configuration (thanks to @andyjansson).
• Fixed resolveConfig for a Root node without a source property
  (thanks to @darthmaim).
• Improved radial gradient handling (thanks to @PigCan).
• stylehacks now properly accounts for vendor prefixes
  (thanks to @evilebottnawi).