Plotting for coherence, parfor for PAC statistics, bispectral TDE

[nguyen-td]

• Added aCOH and iCOH as a plotting option, they are also available through the GUI
• Flipped y-axis of the matrix plot
• Added butterfly (frequency x connectivity) plots for all FC but PAC (for PAC, we have specified f1 and f2 for the computation already)
• Added bispectral time delay estimation
  • Available through pop_roi_connect, calls roi_tde
  • Simulation script is available in the new /simulations folder (we can put Franziska's simulation in there at some point)
  • Documentation included
• PAC statistics will only be based on the unnormalized bispectrum, not the normalized anymore
• Slightly changed our small unit test in /test_pipes/test_pac.m to account for floating point errors

Butterfly plot (from pipeline_connectivity.m)

Time delay estimation (from test_tde.m)