add executable for upcoming command line tools
use docopts for usage text and option parsing
command line options for help and version output
better versions and help
create bag in target dir
spacing in options message
changed a few things in console tools re: argument handling
add validation to command line tool
minor changes to document output, and comments, remove tagmanifest from datafile add code
compact help/version
support for writing data files directly into bag_path/data
a little interface reorg
actually add bag and tag files when requested
tag manifest command
note about tag files
better delete/remove commands; some comments for structure.
delete/remove for console tools; rework command structure; better delete for tag files