Merge pull request #37 from dulmandakh/rn-0.57

depends on react-native@^0.57

package.json

   },
   "peerDependencies": {
     "react": "^16.0",
-    "react-native": "^0.56"
+    "react-native": "^0.57"
   },
   "dependencies": {
     "escape-string-regexp": "^1.0.5",
   },
   "devDependencies": {
     "flow-bin": "^0.80.0",
-    "react-native": "^0.56"
+    "react-native": "^0.57"
   }
 }