Add colors to NVTX ranges

Description

This enables colored timelines in Nsight systems which helps to identify more easily the different regions. The color is chosen by the index of the profiling region. A set of 9 colors is chosen that is designed for the background of text in black with a reasonable difference in color for normal and color-deficient viewers. It is the "light" qualitative color scheme from https://personal.sron.nl/~pault/.