Modify dev_debug_vboot for better usefulness

* Display only the synopsis on stdout
* Keep a verbose log of all activity in the scratch directory.
* Add more checks
* Providing a directory argument will use the images found there instead of
  trying to extract them from the system (for use on host machines).

Change-Id: I065a18c9467c625cc33484ee5556d955dc79b01d


Get a root shell and run "dev_debug_vboot". You should see nicer output.

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2 files changed