Comment 231 for bug 2059809

I'm adding this for Zigo, but it may help other people. It's a very minimal squashed set of patches to get format_inspector into glance for older versions which would require tons of backports to make clean. It's applied against roughly train timeframe.

I'm adding this as a file not a patch, so use at your discretion (or as a guide). It has not gone through our testing yet, only unit tests. It doesn't bring all the testing for format_inspector (like we're doing for nova and cinder) but does bring the tests that confirms glance uses it properly.