Changed to a more realistic way of measuring the performance.

Most likely nobody resolves the same type 1.000.000 times in a row, it is more realistic that the container will switch between resolving the different types. This prevents some (no names mentioned) containers from cheating by optimizing for an unrealistic scenario, just to look good in the test.

PS. Sorry it seems like the change in indentation makes a diff pretty unclear what have been changed. The only thing I have changed is that I have combined the MeasureTransient(), MeasureSingleton() and MeasureCombined() into one method called MeasurePerformance. It just switches between the three when resolving (just a bit more realistic).