Delta Halfway Through Restructuring - WSJ  NEW YORK (Reuters) - Delta Air Lines &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=DAL.N target=/stocks/quickinfo/fullquote"&gt;DAL.N&lt;/A&gt;, still hoping  to avoid filing for bankruptcy, has completed about half its  planned restructuring, the Wall Street Journal reported on  Tuesday.