JCLOUDS-457: limit body size for specific test

For each test, we were forcing the server to discard the content of
the request body on @BeforeMethod. We need to do this on tests with a
huge body, but it may interfere with other tests which actually use
the body data.  To fix this problem, we moved the body limit
restriction to the tests that require it.
JCLOUDS-457: Added initiateJob

Now the Glacier client supports the initiateJob operation.