Implement a threshold for the color maps (noise removal).

Export color map data as a matrix file.

When removing an ms run data set, if the plot widgets are empty, close them.

In the About dialog, set some menus to download mass spectrometric data
from ProteomeXchange.

Attention to the ionization level of the formula in the isotopic cluster
calculation

SavGol filter if required after mz integration.

Add a fraction of y axis below the y=0 line so that the base line if visible.

