9.0.0

• Removed: transform option
  (#250)
• Removed: pkg-resolve is no longer a dependency; this should fix some issues
  with webpack. jspm users must manually install pkg-resolve if they want to
  load jspm modules (see https://github.com/postcss/postcss-import#jspm-usage
  for more info) (#243)
• Changed: If a file is not found, it will now throw an error instead of just
  raising a warning (#247)
• Changed: If a custom resolver does not return an absolute path, the default
  resolver will be applied to the returned path.
  (#249)
• Changed: postcss-import will try to guess the correct parser for imported
  files, based on the file extension.
  (#245)
• Changed: Deprecated addDependencyTo option, it is not needed if using
  postcss-loader >= v1.0.0
  (#251)