Merge pull request #172 from aaboyd/master

Update imagemin dependencies to latest version

Author: tcoopman

package.json

@@ -18,11 +18,11 @@
   },
   "dependencies": {
     "imagemin": "^5.3.1",
-    "imagemin-gifsicle": "^5.2.0",
-    "imagemin-mozjpeg": "^7.0.0",
-    "imagemin-optipng": "^5.2.1",
+    "imagemin-gifsicle": "^6.0.0",
+    "imagemin-mozjpeg": "^8.0.0",
+    "imagemin-optipng": "^6.0.0",
     "imagemin-pngquant": "^6.0.0",
-    "imagemin-svgo": "^6.0.0",
+    "imagemin-svgo": "^7.0.0",
     "imagemin-webp": "^4.1.0",
     "loader-utils": "^1.1.0",
     "object-assign": "^4.1.1"