Solved issue with title alignment (#14)

Author: alvaromb

lib/RouteMapper.js

@@ -73,15 +73,26 @@ export function titleRouteMapperGenerator (TitleComponent, styles, topNavigator)
 export class CenteredText extends React.Component {
   render () {
     return (
-      <View style={{flex: 1, flexDirection: 'row', alignItems: 'center'}}>
-        <Text style={this.props.style}>
+      <View style={titleStyles.container}>
+        <Text style={[titleStyles.title, this.props.style]}>
           {this.props.children}
         </Text>
       </View>
     )
   }
 }
 
+const titleStyles = StyleSheet.create({
+  container: {
+    flex: 1,
+    flexDirection: 'row',
+    alignItems: 'center',
+  },
+  title: {
+    textAlign: (Platform.OS === 'ios') ? 'center' : 'left',
+  }
+})
+
 const defaultStyles = StyleSheet.create({
   back: {
     flex: 1,