Print of version number

[Andreas Sjödin]

It would be convenient to easily see which version that is installed usign doepipeline --version

[davve2]

parser.add_argument("--version", action='store_true', help=argparse.SUPPRESS)

if args.version:
print("{name}: version {version}".format(name=pkgname,version=version))
exit()

[Andreas Sjödin]

this was added in #30