3.2.0 release (#133)
3.2.0 release (#133)

* Add signature auth for endpoints which support it. (#132)

* Update build file to list type safety issues for later resolution.

* Bump version: 3.0.0 → 3.1.0

* Add signature auth for endpoints which support it.

* Update changelog.

* Add release version to CHANGELOG.md

Nexmo/nexmo-java,Nexmo/nexmo-java-sdk