Release 2.0.0

[cwjohnston]

Description

Release new major version with breaking changes.

Motivation and Context

Ship changes which disable built-in filter methods by default, as described in #134

How Has This Been Tested?

Gem artifact has been tested against updated handler plugin in my lab.

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [x] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.
• [x] I have updated the Changelog following the conventions laid out on Keep A Changelog

Known Caveats

Existing sensu-plugins projects will need dependencies on this project updated to ~> 2.0 or similar.