Update to Android Studio 0.5.7

Applied similar changes to the ones made for the other CBL projects.

Please note that, in order to build an app that includes both couchbase-lite-android and couchbase-lite-android-ektorp as submodules with the latest tools, I had to give this project a unique library name. Otherwise, you get
```
Error: more than one library with package name 'com.couchbase.lite'
```
when you try to build. So, I updated the package name in the manifest to `com.couchbase.lite.ektorp`. I don't think this affects anything else, but hopefully you can confirm.