Minor readme tweak
Add unit test to detect issue #164. Also enhance test to use public API.

https://github.com/couchbase/couchbase-lite-android/issues/164
add testDocumentCache() in attempt to repro issue #164, but in this case it did not detect any issues.
temporarily remove document cache from Database

The minimal set of changes required to remove the document cache from
the Database class. It's ugly, but it should be temporary (until the
cache is invalidated everywhere it needs to be).

See couchbase/couchbase-lite-android#164.
Revert "temporarily remove document cache from Database"

This reverts commit f1f8b94ecf9d1d1aa84fa1395927b746eca02b44.
Fix the issue detected in test case added in commit 68bd39a.  There were TODO's in the code that had not been ported over from iOS. Related to issue #164.

https://github.com/couchbase/couchbase-lite-android/issues/164
Test that reproduces issue in forceInsert where it was not sending out a change notification with the correct conflict state.

Noticed this issue while looking at the forceInsert method and seeing TODO's in the code.
Test that fixes issue in forceInsert where it was not sending out a change notification with the correct conflict state.

Unit test in previous commit now passes.
Write test that reproduces issue #24.  Also rewrite test to run faster and be simpler.  Minor change to ChangeTracker to support being inspected by test.

https://github.com/couchbase/couchbase-lite-android-core/issues/24
Fix for issue #24.  Unit test added in last commit now passes.

https://github.com/couchbase/couchbase-lite-android-core/issues/24
Write test that reproduces issue #24.  Also rewrite test to run faster and be simpler.  Minor change to ChangeTracker to support being inspected by test.

https://github.com/couchbase/couchbase-lite-android-core/issues/24
Fix for issue #24.  Unit test added in last commit now passes.

https://github.com/couchbase/couchbase-lite-android-core/issues/24
Share code between testChangeTrackerBackoffInvalidJson() and testChangeTrackerBackoffExceptions()
fix NullPointerException in Document.getRevision()

If you try to get a specific revision using Document.getRevision, but
the current revision has never been retrieved (and so currentRevision is
null), a NullPointerException is thrown.
Merge pull request #25 from mjq/doc_rev_npe

Fix NullPointerException in Document.getRevision()
fix NullPointerException in Document.getRevision()

If you try to get a specific revision using Document.getRevision, but
the current revision has never been retrieved (and so currentRevision is
null), a NullPointerException is thrown.
synchronize access to Database's changeListeners list

Iteration over the changeListeners in Database.notifyChange can throw a
ConcurrentModificationException if addChangeListener or
removeChangeListener is called from another thread.
Merge pull request #26 from mjq/sync_listeners

synchronize access to Database's changeListeners list
Write test case to try to repro issue #165.  Found bugs in both the Database.delete() and the Manager.getExistingDatabase() methods.

https://github.com/couchbase/couchbase-lite-android/issues/165
When deleting a db, it needs to remove it from the manager's list of cached dbs.

https://github.com/couchbase/couchbase-lite-android/issues/165