Update README.md

100.3.0 updates

Author: mhdostal

README.md

@@ -12,8 +12,8 @@ Toolkit components that will simplify your iOS app development with ArcGIS Runti
 * [TimeSlider](Documentation/TimeSlider)
 
 ## Requirements
-* [ArcGIS Runtime SDK for iOS](https://developers.arcgis.com/en/ios/) 100.2.1 (or higher)
-* Xcode 9 (or higher)
+* [ArcGIS Runtime SDK for iOS](https://developers.arcgis.com/en/ios/) 100.3.0 (or higher)
+* Xcode 9.3 (or higher)
 * Apple iOS SDK 10 (or higher)
 
 ## Instructions