Update lesshint to version 6.0.0 (#38)

Author: greenkeeper[bot]

package.json

@@ -11,7 +11,7 @@
   "dependencies": {
     "atom-linter": "^10.0.0",
     "atom-package-deps": "^4.0.1",
-    "lesshint": "^5.0.0"
+    "lesshint": "^6.0.0"
   },
   "devDependencies": {
     "babel-eslint": "^10.0.0",