Update confuse to 1.7.0

[pyup-bot]

This PR updates confuse from 1.4.0 to 1.7.0.

Changelog

1.6.0

''''''

- A new `Configuration.reload` method makes it convenient to reload and
re-parse all YAML files from the file system.

1.5.0

''''''

- A new `MappingValues` template behaves like `Sequence` but for mappings with
arbitrary keys.
- A new `Optional` template allows other templates to be null.
- `Filename` templates now have an option to resolve relative to a specific
directory. Also, configuration sources now have a corresponding global
option to resolve relative to the base configuration directory instead of
the location of the specific configuration file.
- There is a better error message for `Sequence` templates when the data from
the configuration is not a sequence.

Links

• PyPI: https://pypi.org/project/confuse
• Changelog: https://pyup.io/changelogs/confuse/
• Repo: https://github.com/beetbox/confuse