DERBY-6590 Make JUnit tests run the fixtures in a deterministic order.

A new test suite class is introduced to replace the standard JUnit
TestSuite: BaseTestSuite. From its Javadoc:

/**
 * Derby replacement for TestSuite. This version, when provided with a
 * {@code Class} argument in a constructor or method, wraps a {@code TestSuite}
 * around a lexicographically sorted set of fixtures (i.e. test cases) to avoid
 * random fixture ordering (after Java 6). Its usage is similar to the original
 * JUnit TestSuite class.
 */

The old TestConfiguration#orderedSuite has been removed. Import
sections have been updated.

git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/trunk@1608782 13f79535-47bb-0310-9956-ffa450edef68