COMMODITIES-Oil flat, wheat up after mostly soft week for commods

* Brent crude flat at around $113; US crude up for 7th week * Wheat surges on strong US exports * Arabica coffee up on continued fears of coffee "leaf rust" * Copper down as Chile's Collahuasi mine raises output * Gold's safe-haven allure dimmed by Germany's bullish data By Barani Krishnan NEW YORK, Jan 25 (Reuters) - Oil held steady on Friday after robust German data bolstered hopes for global economic recovery and wheat and coffee rallied, muting the week's losses in c