Log Message:
Update to duplicity-0.5.18.

New in v0.5.18 (2009/05/20)
---------------------------
Added support for RackSpace's CloudFiles, cf+http.
Added support for Tahoe-LAFS
patch #6743: Tahoe backend for duplicity
Only half of this bug is fixed but it's still useful.
bug #21792: pipe call fails with an error OSError:
            [Errno 24] Too many open files
Changed from using ulimit external command to
 resource.getrlimit to check open files limit.

New in v0.5.17 (2009/05/04)
---------------------------
Removed one line of code left from some testing that I
 did that caused a crash when the target dir was empty
 and collection-status was requested.
Moved from using the df command to get temp space
 availability to Python's os.statvfs() call.  Not all
 df commands work the same way.
patch #6813: Making changelist easy to read
patch #6814: Ignore comments in filelists

New in v0.5.16 (2009/04/21)
---------------------------
bug #24825: duplicity warn on insufficient TMPDIR
            space availability and low max open
            file limits pre-backup.
bug #25594: wrong backup statistics
bug #25976: Password requested when not needed.
patch #6806: More graceful handling of old
             --short-filename files
Added tilde and variable expansion to the source or
target argument that is not a URL.

New in v0.5.15 (2009/04/09)
---------------------------
FTP backend was failing on PureFTPd when the "-x ''"
 option was removed from the second ncftpls popen, a fix
 that was implemented due to bug #24741.  This fix does
 the ls in one pass by extracting the last entry on the
 'ls -l' listing.
If a file is unreadable due to access rights or other
 non-fatal errors, put out error message and continue
 rather than dying messily with a traceback.
Added tilde '~' expansion and variable expansion in the
 options that require a filename.  You can now have this
 "--archive-dir=~/ArchDir/$SYSNAME" if you need it.  No
 expansion is applied to the source or target URL's.
Fixed problem I caused, again, where sys.exit() was
 trapping instead of exiting.  Added big note to not
 to do that again.

New in v0.5.14 (2009/04/02)
---------------------------
After email voting among known duplicity contributors,
 the decision was reached to revert to the GPL Version 2
 license, so with their consensus, duplicity is now under
 GPL Version 2.
Revert to calling NcFTP utilities (ls, get, put) directly
 rather than scripting ncftp via pexpect by reverting to the
 0.5.07 version of ftpbackend.py.
Changed fatal error regarding version 3.2.0 of ncftpput to
 warning level since it has been reported that the problem
 does not occur on most distributions.

Changed from log.Log with numbered log levels to log.Debug,
log.Info, log.Notice, log.Warn, log.FatalError.
The -vN option has not changed.  Verbosity may also be one
 of: character [ewnid], or word ['error', 'warning', 'notice',
 'info', 'debug'].  The default is 4 (Notice).  The options
 -v4, -vn, and -vnotice are functionally equivalent, as are
 the mixed-case versions, -vN, -vNotice, -vNOTICE.
Normalized include statements and tried to insure that all
 duplicity includes were from the duplicity module.
patch #6790: Add --exclude-if-present

New in v0.5.13 (2009/03/26)
---------------------------
Add more error detection to FTP backend.
Fix backends so sleep does not occur after last retry.
Fix so BackendException does not cause traceback except when
verbosity is at level 5 or higher (Info level).
Adjust log levels so some errors show up with default verbosity.
Fixed bug where an extra comma caused a traceback during a warning
 about unnecessary sig files.  Plus fixed print so the real filename
 would show up and not a Python object representation.
Add Changelog.GNU to website and distribution to add a bit of detail
 showing the CVS changes via rcs2log.  Added dist/mkGNUChangelog.sh.
bug #22908: Don't block gpg-agent
To fix the above, --use-agent was added as a command line option.
 When this is specified and asymetric encryption is enabled, then all
 GnuPG passphrases will come from the gpg-agent or equivalent program
 and no passphrase prompt will be issued.
bug #25787: Usernames with escaped @-sign are not handled properly
bug #25976: Password requested when not needed.
patch #6787: import duplicity.GnuPGInterface explicitly

New in v0.5.12 (2009/03/15)
---------------------------
bug #25838: Backup fails / ncftp - remote file already exists
With this fix we also get resume in ftp get/put.  If a put or
 get fails part of the way through, ncftp will resume on the
 next retry.
bug #25853: duplicity fails with boto passwords coming from ~/.boto
patch #6773: Make user name optional in rsync backend
GPG errors will no longer cause tracebacks, but will produce a
 log entry, from gpg, similar to the following:
===== Begin GnuPG log =====
gpg: BAD0BAD0: skipped: public key not found
gpg: [stdin]: encryption failed: public key not found
===== End GnuPG log =====
This will let the user know what really caused the GPG process
to fail, and what really caused errors like 'broken pipe'.

New in v0.5.11 (2009/03/08)
---------------------------
bug #25787: Usernames with @-sign are not handled properly
Bug #333057: GnuPGInterface prints exit statuses incorrectly
bug #25696: ncftp error w/0.5.09 -- nested target directories
bug #15664: When restoring backup: "OverflowError:
            long int too large to convert to int"
patch #6761: More robust pexpect handling of SSH authentication
patch #6762: Wrong exit() used for 2.3/2.4 Python