Merge pull request #44 from ipdb/greenkeeper/gulp-htmlmin-4.0.0

Update gulp-htmlmin to the latest version 🚀

Author: kremalicious

package.json

@@ -54,7 +54,7 @@
     "gulp-cli": "^2.0.0",
     "gulp-concat": "^2.6.0",
     "gulp-header": "^1.8.9",
-    "gulp-htmlmin": "^3.0.0",
+    "gulp-htmlmin": "^4.0.0",
     "gulp-if": "^2.0.2",
     "gulp-imagemin": "^4.0.0",
     "gulp-include": "^2.0.2",