Commit only every 100 messages
Add a progress bar
Print number of items processed

Not using the progressbar module because we're more interested in a
count of items processed than a representation of percentage to handle
(which takes a while to find out on large mboxes, or on multiple files)
Move old scripts out of way
Merge commit 'refs/gh-pull/remotes/origin/4'

Conflicts:
	bugzilla-email-recovery/extract.py
Record if a bug is a security issue

We parse this information from the email body, and then save it as
either a "Y" or "N"