Log Message:
update to 0.6.3.1

Fixed:
- fixed detectors fix incorrectly fixed in bugfix release 0.6.2
- added note to upgrading doc for detectors fix in 0.6.2
- added script to help migrating queries from pre-0.6 trackers
- fixed "documentation" of getnodeids in roundup.hyperdb
- added flush() to DevNull (sf bug #835365)
- fixed javascript for help window for only one checkbox case
- Date +/- Interval now works, and Date - Date also works
- handle socket timeout exception (thanks Marcus Priesch)
- fixed retirement of items in rdbms imports (sf bug 841355)
- fixed bug in looking up journal of newly-created items in *dbm backends