* PEP8 applied to the docstrings
* deprecated backupExec setting and moved importing the rdiff_backup module to
  the top module
I messed everything up.
* added distribution DEPENDENCIES file
* added support for master YAML config file
* build pre and post hook processing system
* renamed run_job() to run_command as run_job() somewhat collides with the notion that jobs.d contains backup jobs
* changed --remove-older-than functionality to work with hooks system
changed comments only
bug fixes and tidyness for ARIBackup core features
* no longer calling rdiff_backup module directly as it conflates logging and exiting, making it difficult to catch errors and perform clean up; instead calling rdiff-backup with _run_command()
* renamed AriBackup to ARIBackup because ARI is not a word
* changed constructor argument order to put label first since it seems most significant
* made remote_user overrideable
* got pre and post hooks actually working!
* _run_command() can now take str or list as its command arg (facilitates using it to call rdiff-backup)
* fixed missing import sys in logger
* added rdiff_backup_path setting
* PEP8-ification in progress of the LVMBackup class
* in general trying to improve readability
Finished PEP8-ifying the LVMBackup class
LVMBackup now uses pre and post job hooks
LVMBackup no longer duplicates so much code from ARIBackup._run_backup()
Snapshot is one word not two. ;)
fixed constructor for LVMBackup class to include correct number of parameters
fixed typos
general bug fixes and improvements for LVMBackup class
* improved wrapping for some comments
* added state tracking for snapshots (i.e. don't try to remove a snapshot you didn't actually create)
* added ability to pass the top level source dir as an argument tor
  _run_backup() in the base class so that mirrors of snapshots look more tidy
* removed the cooking of the self.lv_list as what it was trying to solve was
  solved by making self.lv_snapshots a dict.
* added tracking for the creation and destruction of mount points
* fixed bug where trying to mount a snapshot would result in a syntax error
* fixed bug where no errors were thrown if the moint point we intend to use
  already is being used as a mount point
* moved ari_backup.py to __init__.py to make this module easier to import
* clean up via post hooks now happens on KeyboardInterrupt
* stderr output from subprocesses is now logging at WARNING to prevent lots
  of console spam from output that happens even when the process returns an
  exit code of zero.
* moved all my work into the jonathan_refactor branch rather than continuing to
  work in the branch where Randy messed everything up ;)
* removed now unncessary comments
Removed all hard exits so that post hooks can always run
* no longer exiting abruptly on failure to execute a command
* no longer exiting on parsing an unknown config key
* removed exit() function from base module
* removed unused import of sys from base module
started adding features to backup data to a NexentaStor appliance
* fixed bug where NexentaLVMBackup class just being instantiated would cause an infinite loop
* added snapshot_suffix setting
* general bug fixes to NexentaLVMBackup class
Reverted to not using the -l option with umount as it doesn't address the root problem of not waiting for subprocesses to exit on KeyboardInterrupt
Added features to manage the workflow of ZFS snapshots
* ARIBackup._run_command() now returns a tuple with stdout and stderr
* replaced anything that said nexenta with zfs since our approach to ZFS
  snapshot management is no longer specific to Nexenta
Apparently some of the changes described in the last commit didn't make it
last time because I forgot to commit with -a. :|

Including the changes likely described in the last commit, we have:
* Removed unncessary default value for error_case for
  ARIBackup._remove_older_than() since it should only be called as a post hook
  and post hooks always include a value for error_case.
* fixed argument ordering in the constructors of the subclasses
* added zfs_snapshot_prefix setting with a default to 'ari-backup-'
* general bug fixes and refinement to the ZFSLVMBackup class
only small cosmetic changes
fixed bug where input wasn't properly sanitized from a zfs get