updated to font-awesome 5 (#181)

package.json

@@ -7,11 +7,11 @@
     "prod": "node_modules/.bin/encore production"
   },
   "devDependencies": {
+    "@fortawesome/fontawesome-free": "^5.1.0",
     "@symfony/webpack-encore": "^0.20.1",
     "bootstrap-sass": "^3.3.7",
     "bootstrap-select": "^1.13.1",
     "daterangepicker": "^3.0.3",
-    "font-awesome": "^4.7.0",
     "icheck": "^1.0.2",
     "jquery": "^3.3.1",
     "jquery-slimscroll": "^1.3.8",