chore(package): update html-minifier to version 1.4.0

http://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -48,7 +48,7 @@
     "gulp-useref": "~3.0.4",
     "gulp-util": "~3.0.7",
     "gulp-watch": "~4.3.5",
-    "html-minifier": "~1.3.1",
+    "html-minifier": "~1.4.0",
     "isparta": "~4.0.0",
     "karma": "0.13.22",
     "karma-browserify": "~5.0.3",