Added test of argument "distribution" in Ãpipe_control.error_analysis.monte_carlo_create_data().
This is to make sure that a wrong argument is not passed into the function.
Task #7882 (https://gna.org/task/?7882): Implement Monte-Carlo simulation, where errors are generated with width of standard deviation or residuals.): Implement Monte-Carlo simulation, where errors are generated with width of standard deviation or residuals.
