Remove usages of util.TestException

[Kirk Lund <kl...@pivotal.io>]

If you find yourself working on any dunit or other test using
*util.TestException* please convert to using *java.lang.AssertionError* (by
using org.junit.Asssert.fail or whatever).

1) remove "import util.TestException;"
2) replace "throw new TestException" with "fail" or "throw new
AssertionError"
3) extra credit: change it from if-then-else to a single assert statement ;)
4) extra credit: if the test is catching Exception and rethrowing as
TestException, remove the try-catch and add throws Exception to the method

util.TestException is another Hydra class and we should avoid repackaging
any Hydra classes when we repackage to org.apache.geode.

-Kirk