Before this change if a pool had an alias configured, the information would not be
made public in the API. This commit adds the alias key in the pool object for each
pool if configured. The alias key can be abscent, a string or an one or multiple
array of strings. The value of the alias is copied from the configuration and can
represent another name for the pool, or another configured pool.
Previously all of the spec tests for VM Pooler were all together in the specs
directory. However some tests require a working local Redis server to operate
and other instead mock all external dependencies. This commit splits the test
files between unit and integration, where integration tests require a working
Redis instance, and unit tests do not. This commit also removes the root
`vmpooler` directory as it is not required. The tests rake test still operates
correctly.
This commit also adds the mock_redis library for testing for the pool_manager.