change the name of Yardstick results file and some log msg

change the name of Yardstick results file and some log msg

JIRA: DOVETAIL-428

1. Change the name of Yardstick result file from opnfv_yardstick_tc019.out to
   dovetail.ha.tc001.out. Because opnfv_yardstick_tc019 is the name defined in
   Yardstick and dovetail.ha.tc001 is the name defined in Dovetail.
2. Check whether the file exists before reporting the results are stored in file.
3. Delete test cases vping_ssh, vping_userdata and sdnvpn.tc003 from the testsuite
   proposed_tests.

Change-Id: I4cb16947729479616a03abd9e91b76f9a41a949c
Signed-off-by: xudan <xudan16@huawei.com>