Bugfix - Typos

Summary:
Fixed few typos in `./Examples` and `./Libraries` folders.
Closes https://github.com/facebook/react-native/pull/4788

Reviewed By: svcscm

Differential Revision: D2759918

Pulled By: androidtrunkagent

fb-gh-sync-id: d692b5c7f561822353e522f9d4dfde7e60b491cf

Libraries/Text/RCTTextField.m

@@ -58,7 +58,7 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:(NSCoder *)aDecoder)
                                eventCount:_nativeEventCount];
 }
 
-// This method is overriden for `onKeyPress`. The manager
+// This method is overridden for `onKeyPress`. The manager
 // will not send a keyPress for text that was pasted.
 - (void)paste:(id)sender
 {

Libraries/Text/Text.js

@@ -71,7 +71,7 @@ const viewConfig = {
 const Text = React.createClass({
   propTypes: {
     /**
-     * Used to truncate the text with an elipsis after computing the text
+     * Used to truncate the text with an ellipsis after computing the text
      * layout, including line wrapping, such that the total number of lines
      * does not exceed this number.
      */