Configurable gamma and luminance range

[dekuenstle]

Instead of either the monitor gamma or linear luminance, it might be preferable to select a fixed gamma, e.g. 2.0 or 2.2, and a fixed luminance range ( see also #4 ).
This customization could allow more reproducible experiments on different monitor instances or even models. Especially with LCDs, the luminance curve rarely follows a power function of actually gamma 2.2.

These configurations could be added to the monitor center (#10).