[fix: #9] Delete pe unit

Author: James Kolce

lib/compile.js

@@ -9,7 +9,6 @@ module.exports = (file) => {
   return postcss([
     require('postcss-lh'),
     require('postcss-pr'),
-    require('postcss-pe'),
     require('postcss-custom-media'),
     require('postcss-media-minmax'),
     require('autoprefixer')

package.json

@@ -19,7 +19,6 @@
     "postcss-custom-media": "^5.0.1",
     "postcss-lh": "^1.1.0",
     "postcss-media-minmax": "^2.1.2",
-    "postcss-pe": "^1.0.0",
     "postcss-pr": "^1.0.0"
   },
   "devDependencies": {