Remove test changes_limitByOne_dbChangesMustReturnedAndLimitedByOne

This test is testing what the changes feed on Couch and Cloudant
returns rather than the library. Useful for understanding the
behaviour, but not required in the sync-android test suite.

FB 23931
Separate Java SE and Android build artifacts.

This allows developers to use our libraries on Java SE or Android platforms without bringing in
unnecessary extra dependencies.

There are now three sub-projects:

* sync-core
* sync-android
* sync-javase

This results in the following jars being published to the maven repo:

* cloudant-sync-datastore-core
* cloudant-sync-datastore-android
* cloudant-sync-datastore-javase