Make bash comple command best effort to authorize

If authorization fails for the complete command, generate the bash complete anyway.
* Added best_effort flag to command
* Attempts to authorize for bash complete, but if it fails, it tries anyway

Change-Id: I796258f8044f42abc6a51164d920a26f73397962
Partial-Bug: #1283550
Merge "Make bash comple command best effort to authorize"