FT_TIMELOCKBASELINE performs baseline correction for ERF and ERP data

 Use as
    [timelock] = ft_timelockbaseline(cfg, timelock)
 where the timelock data comes from FT_TIMELOCKANALYSIS and the
 configuration should contain
   cfg.baseline     = [begin end] (default = 'no')
   cfg.channel      = cell-array, see FT_CHANNELSELECTION
   cfg.parameter    = field for which to apply baseline normalization, or
                      cell array of strings to specify multiple fields to normalize
                      (default = 'avg')
 To facilitate data-handling and distributed computing you can use
   cfg.inputfile   =  ...
   cfg.outputfile  =  ...
 If you specify one of these (or both) the input data will be read from a *.mat
 file on disk and/or the output data will be written to a *.mat file. These mat
 files should contain only a single variable, corresponding with the
 input/output structure.

 See also FT_TIMELOCKANALYSIS, FT_FREQBASELINE, FT_TIMELOCKGRANDAVERAGE