By Silke Koltrowitz ZURICH (Reuters) -Credit Suisse shook up its board on Monday, including the departure of its influential vice chair Severin Schwan, as it attempts to draw a line under a series of damaging scandals. Switzerland’s second largest bank said that Schwan, 54, who was its lead independent director as well as chief executive of Roche, would not stand for re-election to the board of directors at Credit Suisse’s annual general meeting on April 29. Schwan faced criticism for leading the Swiss pharmaceuticals firm while at the same time acting as vice chair of Credit Suisse, a demandi…