test case 0  ...............................................................
python optimization.py -b 2010-01-01 -e 2010-12-31 -x GOOG AAPL GLD XOM 

test case 1  ...............................................................
python optimization.py -b 2008-01-01 -e 2009-12-31 -x SPY GLD

test case 2  ...............................................................
python optimization.py -b 2011-02-01 -e 2012-08-31 -x  JPM AAPL INTC XOM 

test case 3  ...............................................................
python optimization.py -b 2011-02-01 -e 2012-09-04 -x  NSM BIIB 

test case 4  ...............................................................
python optimization.py -b 2011-02-01 -e 2012-08-31 -x  AXP HPQ IBM HNZ