Neither Cassandra nor Elasticsearch starts reliably on Windows. This
commit adds a custom class rule to the associated sample application
tests to skip them on Windows. A class rule is used rather than a
Unit assumption as we want to avoid starting Elasticsearch (done by
the application context) and Cassandra (done by a test execution
listener) and an assumption would be too late.
By default, Elasticsearch writes it data to ./data. This led to data
being left on the filesystem after a mvn clean which could cause
failures when moving between branches that use different versions of
Elasticsearch.
This commit updates the tests for the Elasticsearch sample and
the Elasticsearch auto-configuration classes to write the
Elasticsearch data and logs into the target directory.