feat(log): Add gateway identifier
feat(log): Add gateway identifier

Closes gravitee-io/issues#683

gravitee-io/gravitee-management-webui,gravitee-io/gravitee-management-webui,gravitee-io/gravitee-management-webui,lauthieb/gravitee-management-webui,lauthieb/gravitee-management-webui,lauthieb/gravitee-management-webui