Cedar-backup3

* Updated copyright statements now that code changed in year 2008.
* Fix two unit test failures when using Python 2.5 (SF 1861878).
- Add new function testtutil.hexFloatLiteralAllowed()
- Fix splittests.TestByteQuantity.testConstructor_004() for 0xAC
- Fix configtests.TestBlankBehavior.testConstructor_006() for 0xAC

* Improve error reporting for managed client action failures.
* Make sure that managed client failure does not kill entire backup.
* Add appendix "Securing Password-less SSH Connection" to user manual.

* Minor documentation tweaks discovered during 3.0 development.
* Add support for a new managed backup feature.
- Add a new <peers> configuration section (PeersConfig)
- Change peers configuration in <stage> to just override <peers>
- Modify stage process to take peers list from peers section (if available)
- Add new configuration in options and remote peers to support remote shells
- Update user manual to discuss managed backup concept and configuration
- Add executeRemoteCommand() and executeManagedAction() on peer.RemotePeer

* Deal properly with programs that localize their output.
- Create new util.sanitizeEnvironment() function to set $LANG=C
- Call new sanitizeEnvironment() function inside util.executeCommand()
- Change extend/split._splitFile() to be more verbose about problems
- Update Extension Architecture Interface to mandate $LANG=C
- Add split unit tests to catch any locale-related regressions
- Thanks to Lukasz Nowak for initial debugging in split extension

* Tweak some docstring markup to work with Epydoc beta 1.
* Apply documentation patch from Lukasz K. Nowak.
- Document that mysql extension can back up remote databases
- Fix typos in extend/sysinfo.py
* Clean up some configuration error messages to be clearer.
- Make sure that reported errors always include enough information
- Add a prefix argument to some of the specialized lists in util.py
* Catch invalid regular expressions in config and filesystem code.
- Add new util.RegexList list to contain only valid regexes
- Use RegexList in config.ConfigDir and config.CollectConfig
- Use RegexList in subversion.RepositoryDir and mbox.MboxDir
- Throw ValueError on bad regex in FilesystemList remove() methods
- Use RegexList in FilesystemList for all lists of patterns

* Fix ongoing problems re-initializing previously-written DVDs
- Even with -Z, growisofs sometimes wouldn't overwrite DVDs
- It turns out that this ONLY happens from cron, not from a terminal
- The solution is to use the undocumented option -use-the-force-luke=tty
- Also corrected dvdwriter to use option "-dry-run" not "--dry-run"