Update VERSION & RELEASENOTES for 7.1.3

NOTE: The version was manually updated in the following files:
* RELEASENOTES.md
* VERSION
* bin/templates/cordova/version
* bin/templates/project/assets/www/cordova.js
* framework/build.gradle
* framework/src/org/apache/cordova/CordovaWebView.java
* package.json

with help from git & bash tricks based on changes in the following
commits for 7.1.2 & 7.1.3-dev versions:
- 725e75fa0d
- f86519b158

FUTURE TBD: it is desired that we can set the version in
one place as discussed in: apache/cordova#50

bin/templates/cordova/version

@@ -20,7 +20,7 @@
 */
 
 // Coho updates this line:
-var VERSION = "7.1.3-dev";
+var VERSION = "7.1.3";
 
 module.exports.version = VERSION;
 

bin/templates/project/assets/www/cordova.js

@@ -19,7 +19,7 @@
  under the License.
 */
 ;(function() {
-var PLATFORM_VERSION_BUILD_LABEL = '7.1.3-dev';
+var PLATFORM_VERSION_BUILD_LABEL = '7.1.3';
 // file: src/scripts/require.js
 
 /* jshint -W079 */