Gannet alpha correction of Glx

Hi Molly,

Here are some papers showing a 2:1 ratio of GM and WM Glu/Glx:

Note that in Gannet 3.1, the 0.5 alpha correction is fixed for any metabolite that is quantified. Since v3.2, the alpha correction is metabolite specific. v3.2 is available on GitHub here.

Mark