Support custom configurations in enterprise dashboard

[treydock]

Pull Request Checklist

Description

Add enterprise_dashboard_custom parameter to sensu class which required adding custom property to sensu_enterprise_dashboard_config type.

Related Issue

Fixes #842

Motivation and Context

Dashboard config supporting custom key/value pairs will allow Puppet module to support configurations more easily without updates to Puppet code.

How Has This Been Tested?

Vagrant sensu-server-enterprise box.

General

• Update README.md with any necessary configuration snippets

• New parameters are documented

• New parameters have tests

• Tests pass - bundle exec rake validate lint spec

[treydock]

Did notice adding the enterprise_dashboard_custom to sensu-server-enterprise.pp resulted in "interval": 5 getting removed from dashboard.json. See no mention of interval in docs except example JSON, the key doesn't appear documented.

BEFORE:

{
  "sensu": [

  ],
  "dashboard": {
    "host": "0.0.0.0",
    "port": 3000,
    "interval": 5,
    "refresh": 5
  }
}

AFTER

{
  "sensu": [

  ],
  "dashboard": {
    "host": "0.0.0.0",
    "port": 3000,
    "refresh": 5,
    "usersOptions": {
      "requireSilencingReason": true
    }
  }
}

Log message:

Notice: /Stage[main]/Sensu::Enterprise::Dashboard/Sensu_enterprise_dashboard_config[sensu-server.example.com]/custom: custom changed 'interval => 5' to 'usersOptions => {"requireSilencingReason"=>true}'

[ghoneycutt]

@ninjasloth22 Does this work for you?