Feature-request: git-bundle --quiet

I started trying to make a stab at implementing this, but the code wasn't standing out for it. Hopefully somebody else has poked at it before:

I'd like to have a --quiet option for git-bundle, such that only errors are sent to stderr, and not the packing progress.

This is towards a better incremental backup of large Git repos, later steps would be easier selection of ranges (writing out markers e.g. to use in the next day's incremental backup), and more fine-grained control of the bundle repack behavior (e.g. don't try hard to repack, backup speed is important)