Added networks directory to gitignore
New functions: times_to_bin_multi, PSTH, recursiveflat

times_to_bin_multi: same as times_to_bin but returns 2D array
PSTH: as the name implies - similar to times_to_bin but doesn't discard
multiple spikes in the same bin
recursiveflat: recursively flattens nested list or array structures
PSTH returns times

also removed an unwanted print statement