Proton-therapy analytical models as first category

[marwin1991]

If we put categoris in this order Proton-therapy analytical models Particle range and stopping power Energy And Momentum Calculators Track Structure

we will use more first page workspace for screens that can handle for categories in a row, because Track Structure will be under Proton-therapy analytical models and both of then are short so they will display without need of scrolling

[grzanka]

Calculators are separate item which should be reflected by the order on the page, apart from that reordering looks as good idea