Check vehicle load for ACISpkt commands

[jazan12]

Suggest this should be included

[Gregg140]

The suggestion is to scan the VR*.backstop file for any ACISPKT commands that may have inadvertently been inserted there.

The place to do this is the backstop_history method "get_VR_bs_cmds" whose function is to read the specified VR*.backstop file supplied by the weekly load tarball in the .../vehicle subdirectory. At read time there should be no ACIPKT commands there.