WebdriverIO tests failing with Appium 1.6


My wdio tests were working fine with Appium 1.4.13 and xcode 7.
Today I updated appium to 1.6 and xcode8.
When I am trying to execute my tests using the grunt task runner, I am getting this error :

Appium server is not running at port: 4723
Starting local Appium server at port: 4723
Running Appium tests with args: [ ‘/tmp/wdio.conf.js’ ]
ERROR: A new session could not be created. Details: Appium’s IosDriver does not support xcode version 8.2.1. Apple has deprecated UIAutomation. Use the “XCUITest” automationName capability instead.

ques : Where do I set the automationName capability. I tried to do that in gruntfile but its not working.