thousands 0.1.3

Adds digit separators to numbers, configurably.
Documentation
# Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog] and this project adheres to
[Semantic Versioning].

[Keep a Changelog]: http://keepachangelog.com/en/1.0.0/
[Semantic Versioning]: http://semver.org/spec/v2.0.0.html

## [0.1.3] - 2019-10-19

### Added
- `Separable::separate_with_underscores` method and
`policies::UNDERSCORE_SEPARATOR` constant.

## [0.1.2] - 2018-09-18

### Fixed
- Github URL in Cargo.toml.

## [0.1.1] - 2018-09-16

### Added
- Doc comment for `policies` module.

## [0.1.0] - 2018-09-16

Initial release.