Errors after postcss-loader update

[vladzhigulsky]

Updated postcss-loader package to the latest version (2.1.6) and now getting the following errors on build.

Unknown error from PostCSS plugin. Your current PostCSS version is 6.0.23, but postcss-cachebuster uses 5.2.18. Perhaps this is the source of the error below.

TypeError: Cannot read property '1' of null at walkThroughtImports (/node_modules/postcss-cachebuster/index.js:86:26)

[seancoyne]

I'm seeing the same using postcss-loader 2.1.2