Split Pipfile parsing to independent library

[gsemet]

Reference: #952.

Parsing à Pipfile using pipenv adds many dependencies (ex: flake8.cli).

Is it possible to split the parsing part from the pipenv CLI into a different package?

I would like to contribute to at least ReadTheDocs and PBR to help them support Pipfile, and that would help a lot if everyone use the same parser.

[techalchemy]

This seems like a good idea, although technically Pipfile parsing is handled by Toml via the Pipfile spec (see pypa/pipfile)

[erinxocon]

@stibbons @techalchemy That repo will eventually contain a parser for Pipfiles once the pipfile spec settles a little. Probably extract it from pipenv.