pip-upgrade-outdated 1.0b1

Command-line tool to updated outdated python packages

# pip_upgrade_outdated

Run `pip install --upgrade` for all outdated packages (`pip list --outdated`).

Allow specifying which version of `pip` to run, and parallel or serial execution of the upgrade step.

### Command line usage

```
usage: pip_upgrade_outdated [-h] [-3 | -2 | --pip_cmd PIP_CMD] [--verbose]
[--dry_run] [--serial] [--version]

Upgrade outdated python packages with pip.

optional arguments:
-h, --help show this help message and exit
-3 use pip3
-2 use pip2
--pip_cmd PIP_CMD use PIP_CMD (default pip)
--verbose, -v may be specified multiple times
--dry_run, -n get list, but don't upgrade
--serial, -s upgrade in serial rather than parallel
--version show program's version number and exit
```

### TODO

* does it work with environment variables?
* need better error handling?
* have it run with `--format columns` when using `--dry_run` and `--verbose`?
* Should the script explicitly return a value to the shell?

### Sources

* code based on https://gist.github.com/serafeimgr/b4ca5d0de63950cc5349d4802d22f3f0
* project structure based on https://gehrcke.de/2014/02/distributing-a-python-command-line-application/