This module implements commands with subtrees of commands.

Suggested use in your project (if you are using git):

- create myproject/extern directory and package:
  export PROJECT=myproject
  mkdir -p $PROJECT/extern
  touch $PROJECT/extern/__init__.py
- add the submodule:
  git submodule add https://github.com/thomasvs/python-command.git $PROJECT/extern/python-command
  pushd
  cd $PROJECT/extern
  ln -sf python-command/command command
  popd
- test if you can import it:
  python -c "from $PROJECT.extern.command import command; print command"
- Commit the result to git
  git add $PROJECT/extern/command
  git commit -m "add python command module" .gitmodules $PROJECT/extern/command