Upgrade SDK to 14.00, fix a few small issues in the example app.

Launch SDK version 13.30

Upgrade to version 13.22

Update to version 13.21

Release SDK version v13.20

  * Improved support for Unity. [Documentation](https://www.appbrain.com/info/help/sdk/unity.html)
  * Automatic SDK initialization. (Calling AppBrain.init() is optional now).
  * Android O compatibility fixes
  * Removed RecyclerView-based ads

Upgrade to SDK release 13.10:

- Added support for 11 more languages, bringing the total to 34.

Update to SDK version 13.00:

- Added preload() function to InterstitialBuilder.
- InterstitialLoader now has onAdLoaded and onAdFailedToLoad callbacks.
- Supports AppBrain mediation (contact us for details).
- Better timeouts for ad conversion rates.

Add description of SDK v12

Update to SDK version 11.20:

* Better performing interstitials
* More accurate identification of users who are likely to install promoted apps
* Better handling of problems caused by devices with buggy Android OS versions

SDK release v11.10