remove unused devDependency: less

Author: alxndrsn

package.json

@@ -79,7 +79,6 @@
     "http-server": "0.12.3",
     "istanbul": "0.4.5",
     "istanbul-coveralls": "1.0.3",
-    "less": "3.9.0",
     "lodash.debounce": "4.0.8",
     "lodash.flatten": "4.4.0",
     "lodash.uniq": "4.5.0",