NF: support slicing of struct
RF+ENH+BK: new implementation of correlation measure; rename splithalf_correlation_measure to correlation_measure
ENH: more informative error message for wrong config
ENH+OPT: disable check for combinations for "half" split
NF+OPT: world-wide disable of check available when slicing
NF: support split of array
NF+OPT: world-wide disable of check available when stacking
NF+STS: searchlight