Merge z scoring methods

adresses #421 (closed)

Added

• Parameter axis in flagZScore (enables calculation along data column axis.)

Changed

• deprecated flagCrossStatistics in favor of flagZScore
• deprecated flagMAD in favor of flagZScore
• deprecated parameters norm_func and model_func of flagZScore in favor of Parameter method

Removed

• Support for ZScoring with function composites resulting in operators other than standard or modified ZScore in flagZScore