MapView to support MKPointAnnotation using new attribute annotate in Map...

Summary:
### MapView to support Pin annotation

    var pinLocation = {
			latitude: property.latitude,
			longitude: property.longitude,
			title: property.title
    };
    this.state = {propertyPoint: pinLocation};
    <MapView style={styles.map} region={this.state.region} annotate={this.state.propertyPoint}>
    </MapView>
![mapview-pinannotation](https://cloud.githubusercontent.com/assets/845379/7100280/6c1ffc08-dfe5-11e4-9d1b-8da6a65da1bc.png)

Closes https://github.com/facebook/react-native/pull/810
Github Author: guru inamdar <guru.inamdar@gmail.com>

Test Plan: Imported from GitHub, without a `Test Plan:` line.

Libraries/Text/RCTText.m

@@ -114,7 +114,9 @@
 - (NSNumber *)reactTagAtPoint:(CGPoint)point
 {
   CGFloat fraction;
-  NSUInteger characterIndex = [_layoutManager characterIndexForPoint:point inTextContainer:_textContainer fractionOfDistanceBetweenInsertionPoints:&fraction];
+  NSUInteger characterIndex = [_layoutManager characterIndexForPoint:point
+                                                     inTextContainer:_textContainer
+                            fractionOfDistanceBetweenInsertionPoints:&fraction];
 
   NSNumber *reactTag = nil;