New release: card.io 5.1.0 for Android

[Jeff Brateman]

Hello from card.io!

We have posted version 5.1.0 of card.io for Android to GitHub (https://github.com/card-io/card.io-Android-SDK). 

From the release notes:

5.1.0
-----
* Add arm64-v8a processor support [#33-source](https://github.com/card-io/card.io-Android-source/issues/33), [#51](https://github.com/card-io/card.io-Android-SDK/issues/51).
* Add x86 processor support [#26-source](https://github.com/card-io/card.io-Android-source/issues/26).
* Add x86_64 processor support.
* Add support for Android 23 new permission model for the Camera permission [#78](https://github.com/card-io/card.io-Android-SDK/issues/78).  When permission is granted, the SDK performs as in previous versions.  When permission is or has already been denied, the SDK falls back to manual entry.  Note: this SDK does not call the `shouldShowRequestPermissionRationale()` method and does not show a rationale.  It is up to the implementor whether or not to show the Camera permission rationale before opening the SDK.
* Populate CardIOActivity.EXTRA_CAPTURED_CARD_IMAGE when confirmation is shown [#10-source](https://github.com/card-io/card.io-Android-source/issues/10).
* Fix issue where setting `EXTRA_KEEP_APPLICATION_THEME` would not create buttons that matched the theme [#24-source](https://github.com/card-io/card.io-Android-source/issues/24).
* Add a default edit text hint color [#22-source](https://github.com/card-io/card.io-Android-source/issues/22).
* Fix leaking IntentReceiver [#76](https://github.com/card-io/card.io-Android-SDK/issues/76).

Thanks!
@cardio