obmc_boot_test.py RESTORE_LAST_STATE and PDU validation.

- Added code to 'Set BMC Power Policy  RESTORE_LAST_STATE' at the
  beginning of each test run.

- Added code to validate PDU parameters if any boot tests are
  specified that require them.

Change-Id: If0f1b4a6bdfeee06530de9d660cb174e313c23a9
Signed-off-by: Michael Walsh <micwalsh@us.ibm.com>
2 files changed