Output total photon number

Display the total photon number for each measurement (and the
difference) in the console, so we can add that to the ProgressReport
Removed integration part at the end, since we can calculate the total
from the Data.
Now discussing the results with Sebastian and Anna.
Adding attenuation and transmission data

Data downloaded from NIST or gotten from Anna Bergamaschi, keeping the
data in the repo so it's self-contained.
Updated plotting for ProgressReport

Spectra are corrected (crudely) with attenuation/transmission data from
NIST, according to discussion with Sebastian/Anna.
Further work needs to be done to have a proper energy calibration of
GOTTHARD, this is something for upcoming experiments.
PlotGOTTHARD gives out plots as PDF so we can directly drag-n-drop then
into Keynote. Also making a superfluous animation :)