Allow React 17 as peer dependency (#168)

Author: lex111

package.json

@@ -62,8 +62,8 @@
     "classnames": "^2.2.5"
   },
   "peerDependencies": {
-    "prop-types": "^15.3.0 || ^16.0.0",
-    "react": "^15.3.0 || ^16.0.0",
-    "react-dom": "^15.3.0 || ^16.0.0"
+    "prop-types": ">= 15.3.0 < 18",
+    "react": ">= 15.3.0 < 18",
+    "react-dom": ">= 15.3.0 < 18"
   }
 }