tests: add unit test case for replication

tests: add unit test case for replication

[Rename get_error test cases to get_error_all to avoid tripping up
scripts that grep for "error:" in test output.  It also reflects the
actual replication API function name better.
-Stefan]

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Signed-off-by: Wang WeiWei <wangww.fnst@cn.fujitsu.com>
Message-id: 1469602913-20979-11-git-send-email-xiecl.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>