Add Pipfile and Pipfile.lock.

[mikecanoy]

Closes #6. Added Pipfile.lock per pypa/pipenv#598.

[reillysiemens]

Hey, @solus-impar, thanks for this PR. I've gone ahead and updated the label for this and the original issue to indicate that this is still an outstanding question for me.

I've not fully decided whether I want to include a Pipfile. My primary hangup comes from the fact that it doesn't really help me with distribution. As Pipfiles are not yet supported in pip proper, the tool most users will use to install this library I'm hesitant. I don't like to include the same information in more than one place if I can get away with it because I'm pretty forgetful and right now i'm using

from pip.req import parse_requirements

in my setup.py to parse the *requirements.txt files. There's no analogue for a Pipfile at the moment, so as far as I can tell I'd have to maintain the *requirements.txt files and the Pipfile... 🙃

If you've got any ideas about how to solve that problem I'm all ears, but until then I think I'm on the fence and main remain there for a little bit. I didn't mark #6 as a Milestone v1.0.0 dependency because I think I'd be OK with shipping before answering this question. I just didn't want to lose track of it altogether.

[RadicalZephyr]

Okay, I did some research into this, and I think right now Pipenv is not aimed at working well with libraries and syncing with the setup.py file.

A good summary can be found in the pipenv docs.

There is one possibility that would involve abandoning all of the *requirements.txt files: pypa/pipenv#1263 (comment)

Unfortunately, I just tried this approach out and after inlining the various dependency file contents into the setup.py file I couldn't get Pipenv to install the dev or test dependencies. Possibly I'm missing something, branch is here: https://github.com/RadicalZephyr/layabout/tree/pipenv

[reillysiemens]

I think I'm actually going to abandon using pipenv or even *requirements.txt files altogether and follow Flask's example by just returning to embedding my requirements directly into setup.py. I'll probably just use lists and extend them for the various extras_require sections.

Thanks for the PR though, @solus-impar. And thanks for the research, @RadicalZephyr! 😁