function  = li_mkliio(nSignal, nTime, sSigName, sFileName)
creating a ".liio" signal-io file from matlab data. Expecting signal data as first argument, a time value as second, a signal name string as third and a file name as fourth argument. There is no output argument. Errors might be reported, though.
Signal data might be a column vector or a matrix where each row represents an outpout at a time in ascending time order.
Time value might be a scalar representing the time step or a 1-d vector with as many rows as in signal data for time stamped signal data values. Time values must be strictly monotonously ascending.
Signal name is the name assigned to the signal inside the newly created file.
File name is the name of the file where the signal will be stored. Might be an absolute path, a relative path or just a plain file name. In latter case the file is writen to current directory.