Add a Handler site_config class method for reading JSON configs
Add a Handler site_config class method for reading JSON configs

kelcecil/sensu-plugins-bitbucket,nyxcharon/sensu-plugins-quay,nyxcharon/sensu-plugins-last-modified,upfluence/sensu-plugin,nyxcharon/sensu-plugins-fleet,sensu-plugins/sensu-plugin,nyxcharon/sensu-plugins-bitbucket,zbintliff/sensu-plugin,somic/sensu-plugin,nyxcharon/sensu-plugins-vault