Add JDK links to exporting for Android

getting_started/workflow/export/exporting_for_android.rst

@@ -15,9 +15,7 @@ http://developer.android.com/sdk/index.html
 Install OpenJDK or Oracle JDK
 -----------------------------
 
-Download and install OpenJDK or Oracle JDK. Version 6 and 8 are known to
-work, some users have reported issues with the jarsigner (used to sign the
-APKs) in JDK 7.
+Download and install [OpenJDK](https://github.com/ojdkbuild/ojdkbuild) or [Oracle JDK](http://www.oracle.com/technetwork/java/javase/downloads/index.html). Versions below JDK 8 may not work, some users have reported issues with the jarsigner (used to sign the APKs) in JDK 7.
 
 Create a debug.keystore
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