Added chi-squared and reduced chi-squared to model class. They are both signals at the moment, so could be slow.
Also added option to make progress bar for as_signal() optional.
fixed missing reference to data of chisq
will have to redo, removed additional changes to be moved to other branches
corrected implementation of chi squared. Reduced still not present
Merge branch 'master' of https://github.com/hyperspy/hyperspy into chi_squared
added reduced chi squared calculations (as a property)
removed unnecessary comments and blank lines
added titles for chisq, red_chisq and dof
added docstrings, fixed as per comments of Francisco
corrected to not throw error with fit_component
added quick chi-squared tests
preliminary added user guide chapter for chi-squared and fixed calls for storing data faster
fixed chi-squared tests to not be as dependent on fit() function
corrected version added in documentation
changed calculations to be meaningful without variance set (assuming usual Bayesian statistics)
fixed tests for chi-squared with Bayesian variance if none defined
leave variance as 1 if not explicitly set, moved chisq calculations to after storing fitting parameters
bug with variance indices passing for chisq calc
Automatic style corrections courtesy of autopep8
changed mapped_parameters -> metadata