TestCluster can currently only be used in a globally shared scope.
This commit adds the ability to use the TestCluster in 3 different
scopes per test-suite. The scopes are 'Global', 'Suite' and 'Test'
where the cluster is shared across all tests, across all test methods or
not at all respectivly.
Subclasses of AbstractIntegrationTest (formerly AbstractSharedClusterTest)
can add an annotation if they need a different scope than Global (default):
```
@ClusterScope(scope=Scope.Suite, numNodes=1)
```
This also allows to specify the number of shared nodes in that TestCluster
that are available when a test starts.
The cleanups in this commit include:
- s/Elasticsearch/ElasticSearch/g on test classes
- Move test classes in org.elasticsearch.test
While testing an async system providing reproducible tests that
use randomized components is a hard task we should at least try to
reestablish the enviroment of a failing test as much as possible.
This commit allows to re-establish the shared 'TestCluster' by
resetting the cluster to a predefined shared state before each test.
Before this commit a tests that is executed in isolation was likely
using a entirely different node enviroment as the failing test since
the 'TestCluster' kept intermediate nodes started by other tests around.
