template functions for basic cellbase

[torbenott]

I would suggest creating template functions to enable core functionality after calling initcb. Template functions could be part of the repository used as default after calling initcb. Users could then copy&modify the template functions and point cellbase to their own functions.

• core functionality: create TrialEvents.mat, create prealigned spikes, plot psth to TrialStart event

• necessary templates: MakeTrialEvents.m; defineEventEpochs.m; script to add a cell or session and plot psth