Bump eslint from 3.19.0 to 6.6.0

Bumps [eslint](https://github.com/eslint/eslint) from 3.19.0 to 6.6.0.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/master/CHANGELOG.md)
- [Commits](eslint/eslint@v3.19.0...v6.6.0)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package.json

@@ -21,7 +21,7 @@
         "watchify": "^3.9.0",
         "uglify-js": "~2.7.5",
         "clean-css-cli": "^4.0.0",
-        "eslint": "^3.13.0"
+        "eslint": "^6.6.0"
     },
     "license": "MIT"
 }