Fixed #15277 -- Cleaned up `ogrinspect` command, added tests and extended...

Fixed #15277 -- Cleaned up `ogrinspect` command, added tests and extended support beyond file-based OGR data sources.  Thanks, willinoed for bug report and jpaulett for initial patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16845 bcc190cf-cafb-0310-a4f2-bffc1f526a37