Question:

How can we measure current per module as shown in the data manual.  An example is given in the table below.  Is it simply turning on and off the clock to the module?

Answer:

When these numbers are taken, we enable the clocking to the module as well as have code continuously running which exercises as much logic in that peripheral as possible.  If you go from running code to maximize the use of a peripheral to disabling the clocking to that peripheral, then you should see a current savings similar to what we have in the datasheet. 

Keep in mind that these numbers are TYPical numbers. Depending on the supply voltage, Fab lot, activity done by the peripheral etc, there will be some variation between what you may measure to what is quoted in the datasheet.