calculate CRF for each channel and session
older version
no 'split sessions' at this stage of analysis

previously, some of blanco's sessions were split (355, 405, 435). for
processed spike data in matarrays, data from split sessions is combined
properly now.
CRF correlation for each channel across sessions
plot CRF corr coefs for all channels

display plots of correlation coefs on one figure
population-wide CRF analysis

Examine mean firing rate across channels, look for correlations with
time
separate functions for coefficient plotting
plot neuronal CRF for each channel

Naka-Rushton function curve fitting, slope, C50, min and max firing rate
calculation.
added plots for abs(C50-30), min and max
renamed
Checks whether artifact-free .ncs files generated

Prints list of missing channels for each session of interest, to screen.
CRF analysis functions
code shared by ROC and CRF analysis
backup- old versions
name update within code
implement shared ROC/CRF routines