Begins to implement unit tests for new flux_point.py code
Adds example for use of flux_point method function
Minor corrections to flux_point.py main script as suggested in comments
Implements further tests - although one is still missing
Adds test data files - probably will remove at a later point when better data available for relevant unit test
updates test_fitter.py
updates flux_point unit tests
Improves differential_flux_point method unit test using published crab fluxes for comparison
Debugging and ensuring unit tests work - needs to be tested with a clean install