Drop delete.end notifications with blank launched_at

We can safely drop delete.end notifications without values for
launched_at because these instances never got launched. Thus,
we'd never expect any usage for them.
Merge pull request #240 from ramielrowe/drop_delete_end_no_launched_at

Drop delete.end notifications with blank launched_at
Better handling of resize issues

Populating flavor details from prep.end turns out to be a bit
too early. If the compute is restarted before the resize has
finished the instance will still be the old size. Thus, an exist
after that will be for the old (and actual) size of the instance.
glance_usage_audit.py gives the summary of all exists within audit period along with details of failed exists. Some refactoring in nova_usage_audit is also included.
incorporated the review changes and optimized the old_images_query
correcting the old_launches query to the optimized one
removing the unwanted old file
Merge pull request #210 from manalilatkar/glance_usage_audit

Glance Usage Audit
Merge pull request #242 from ramielrowe/resize_fixes

Better handling of resize issues
Attempt DB reconnection in callback
Merge pull request #244 from ramielrowe/resize_fixes

Attempt DB reconnection in callback
Implemented multiprocess logging
Merge pull request #245 from anujm/worker_log_fix

Implemented multiprocess logging
Add assertIs to cover py2.6