Environs

Features:

- _Backwards-incompatible_: `Env.read_env` raises a warning instead of
an error when `.env` isn\'t found
([10](https://github.com/sloria/environs/issues/10)). Thanks
[lachlancooper](https://github.com/lachlancooper) for the
suggestion.
- Add optional Django support. Install using
`pip install environs[django]`, which enables `env.dj_db_url` and
`env.dj_email_url`.

Features:

- Fix compatibility with marshmallow 3 beta.

Features:

- Add recurse parameter to Env.read_env
([9](https://github.com/sloria/environs/pull/9)). Thanks
[gthank](https://github.com/gthank) for the PR.

Features:

- Add support for nested prefixes
([8](https://github.com/sloria/environs/pull/8)). Thanks
[gvialetto](https://github.com/gvialetto) for the PR.

Other changes:

- _Backwards-incompatible_: Drop support for Python 3.3 and 3.4.

Features:

- Add `url` parser that returns a `urllib.parse.ParseResult`
([6](https://github.com/sloria/environs/issues/6)). Thanks
[IlyaSemenov](https://github.com/IlyaSemenov) for the suggestion.

Bug fixes:

- Every instance of `Env` gets its own parser map, so calling
`env.parser_for` for one instance doesn\'t affect other instances.

- Add `Env.read_env` method for reading `.env` files.