code: function(container, cb) {
            if (container) {
              var dockcontainer = docker.getContainer(container.Id);
              if (utils.getContainerStatus(container) === "RUNNING") {
                grunt.log
                    .writeln("Found a matched running container, killed it.");
                // Kill it
                dockcontainer.kill(function(e) {
                  if (e) {
                    return callback(e);
                  }
                  cb(null, dockcontainer);
                });
              } else {
                cb(null, dockcontainer);
              }
            } else {
              // Create it
              grunt.log.writeln("No existing container, create a new one.");
              var opts = confImage && confImage.options
                  && confImage.options.create || {};
              opts.Image = utils.qualifiedImageName(tag, options.registry,
                  confImage && confImage.tag);
              opts.name = opts.name || tag;
              docker.createContainer(opts, cb);
            }
          }
docs: Step 2: if no running container, create a new one else kill it