REBASE standard script for setting up ant builds
move SQLCipher helpers to separate library project

This means that the core of Cacheword can be shipped as a simple jar that
only depends on the Android Support v4 jar.  Also, for many users, they
will never need the SQLCipherV3MigrationHelper in their project at all
since they started with SQLCipher v3.

refs #3680 https://dev.guardianproject.info/issues/3680
move defaults out of XML and directly into the relevant classes

These constants are barely used, and are the only thing left that prevent
cacheword from being distributed only as a jar.

refs #3680 https://dev.guardianproject.info/issues/3680