Avoid exact version lock for classnames (#1107)

Fixes #732

Author: supremebeing7

package.json

@@ -80,7 +80,7 @@
     "webpack-dev-server": "2.7.1"
   },
   "dependencies": {
-    "classnames": "2.2.5",
+    "classnames": "^2.2.5",
     "prop-types": "15.5.10",
     "react": "16.4.0",
     "react-dom": "16.4.0",