Testcase 3 Apex compatibility fixes

Testcase 3 Apex compatibility fixes

- Workaround a bug releng in getting opedaylight nodes
- Add some sudo commands because the path is not properly set otherwise
  it seems
- remove needless command that gets ip information from the compute,
  since that is already available from when the command was ran on the
  controller
- Handle attaching the quagga instance to Apex's br-ex ovs bridge

Change-Id: I870f1049d9cce696ec26376a09db5f9e9bac0bf9
Signed-off-by: Romanos Skiadas <rski@intracom-telecom.com>
(cherry picked from commit b5b2a3abd74f84943cf3fab7ca7da591d326661c)