Updated bootstrap.py
Make upgrades appear in undo form again.

The transaction note fix in 1.7.4 caused upgrade transaction to not appear in the undo form.
Merge pull request #54 from 4teamwork/jone-undo

Make upgrades appear in undo form again.
Implement upgrade step directory scanner.
Implement upgrade step directory directive.
Automatically set profile version to latest upgrade version.
Extend UpgradeStep with ``install_upgrade_profile`` method.
Extend importProfile directive with new optional "handler" argument.
Wrap upgrade step handlers with profile information.
Implement marking installed upgrade steps.
Update gatherer to include orphan information.
Highlight orphan upgrade steps in manage view.
Update translations.
Update changelog.
Bump target version to be a feature release.