The Chicago Cubs have given assistant general manager Randy Bush a three-year contract extension.  The 54-year-old was brought into the organization in 2005 as a special assistant to then-GM Jim Hendry.  Bush was promoted in 2006 as assistant general manager, then was bumped up to interim GM when Hendry was fired in August of 2011.  Bush continued to serve as an assistant general manager under current GM Theo Epstein this past season, and will be one of two men to hold the post going forward.  Shiraz Rehman was promoted earlier this month.