This test program will read 1K samples from the ADC,
and send the results in CSV format out via USB CDC.

The test results can be pasted into Excel and analyzed
to better understand the ADC performance.

There appears to be a couple LSB of variation on the ADC
of the LPC1343 Reference Design, including some fairly
large one-off peaks and valleys.

As a result of these tests, and additional flag was added
to the code base to enable the ADC code to optionally take
a number of readings and return an average result, which
helps reduce the effect of individual peaks or dips in the
ADC.

Results of the tests with and without averaging can be
seen in the included excel spreadsheets, showing min, max
and stddev for the range of data captured.

As was expected, the ADC seems to perform better towards the
middle of the range than on the lower end.