ragavi-gains: selection of correlation 1 also shows all antennas

[o-smirnov]

I start with a MeerKAT bandpass plot. This is showing antennas m000-m016 (the "blue" end of the colormap) and corr 0 in its initial state:

Then I click on corr 1. This seems also to display all antennas as a byproduct (the red ones are high-numbered):

[Mulan-94]

Oh yes, I am aware of this. The reason is that there are multiple plots ( per field, spw and correlation ) associated to every single antenna's legend. There is a note on it in the docs here and I'm yet to iron out this.