Plot function for one channel only and zoom temporally

[giossic]

Implement a function to plot just one-channel activity + function that consents to zoom temporally into network dynamics

[giossic]

Done.

[jyotikab]

Works !

[jyotikab]

The colors for left and right are interchanged as compared to the plot - plt_func.plot_fr. The colors should be same as in plot_fr