docs: function update (client) {
    return function update (options) {
      options = options || {};
      const req = {
        url: `${client.baseUrl}/rest/applications/${options.variantId}/installations/${options.installation.id}`,
        body: options.installation,
        method: 'PUT'
      };
  
      return request(client, req)
        .then((response) => {
          if (response.resp.statusCode !== 204) {
            return Promise.reject(response.body);
          }
  
          return Promise.resolve(response.body);
        });
    };
  }