Upgrade examples following to the SDK changes

Author: Bohdan Shulha

README.md

@@ -46,7 +46,7 @@ yarn add bs-platform reason-react bs-react-native
 open BsReactNative;
 
 let app = () =>
- <View style=Style.(style([flex(1.), justifyContent(`center), alignItems(`center)]))>
+ <View style=Style.(style([flex(1.), justifyContent(Center), alignItems(Center)]))>
  <Text value="Reason is awesome!" />
  </View>;
 ```
@@ -96,20 +96,20 @@ open BsReactNative;
 <View
  style=(
  Style.style([
- Style.flexDirection(`column),
+ Style.flexDirection(Column),
  Style.backgroundColor("#6698FF"),
- Style.marginTop(5)
+ Style.marginTop(Pt(5))
  ])
  )
 />;
 
 /* inline styles with a local open */
-<View style=Style.(style([flexDirection(`column), backgroundColor("#6698FF"), marginTop(5)])) />;
+<View style=Style.(style([flexDirection(Column), backgroundColor("#6698FF"), marginTop(Pt(5))])) />;
 
 /* StyleSheets with a local open */
 let styles =
  StyleSheet.create(
- Style.({"wrapper": style([flexDirection(`column), backgroundColor("#6698FF"), marginTop(5)])})
+ Style.({"wrapper": style([flexDirection(Column), backgroundColor("#6698FF"), marginTop(Pt(5))])})
  );
 
 <View style=styles##wrapper />;