An example 'principal_component_analysis' was added to specifically test this functionality. It uses the analytical model.
Fixed two if-calls in `pca_transformation` to match older code and the content of the function.

This reverts commit acf483a1

Split the model comparison to be callable in functions for bayes factors, model weights and justifiability analysis and renamed the overall function

BMC only runs the BME part of BayesInf, split JA into its own function, removed redundant function in MCMC, added to function diagrams

More test for BayesInf, starting tests for MCMC

Some simple fixes for various test, start on testing BayesInf, output directory as changeable parameter in BayesInf